GOP presidential candidates clashed over immigration, government spending and how to handle Russia's Vladimir Putin during Tuesday night's debate. As the night got heated, the audience got involved: here are the must-watch moments. (Ashleigh Joplin and Rebecca Schatz/Fox Business Network) 
 
 The eight top Republican presidential candidates gathered for the fourth debate of the 2016 campaign Tuesday night in Milwaukee. It was a more understated affair than the last GOP debate sponsored by CNBC but still managed to yield some bests and worsts. 
 
 Here are my winners and losers from the night that was: 
 
 Winners 
 
 * Marco Rubio: Rubio's line about welders making more money than philosophy majors will be quoted all over the place in the post-debate analysis. (And, no, it wasn't totally accurate.) Rubio knocked it out of the park when debating military spending and the right role for America in the world with Rand Paul. He got a meatball of a question when asked by the moderators about Hillary Clinton's résumé as compared with his own; he, unsurprisingly, answered it well and easily. Time and time again, he oozed knowledge while appearing entirely relaxed. One nit to pick with Rubio: He can — and did at times Tuesday night — come across as slightly too rehearsed, the student reciting things back to the teacher from memory but without actually understanding what any of it means. 
 
 * Ted Cruz: For the second straight debate, the senator from Texas shone under the bright lights. His line about the tax code having more words than the Bible was a good and memorable one. His repeated denunciations of Washington's "crony" culture will leave a lot of Republican heads nodding in agreement. Cruz proved Tuesday night that of the "outsider" candidates, he is the one best equipped to carry their message going forward. 
 
 * Ben Carson: In the first three debates, I watched in wonder as Carson's numbers kept moving up after what I perceived to be nearly nonexistent performances. But Carson — from his first answer on Tuesday night — was more energetic (that's a pretty low bar given Carson's past performances) and more dialed in than I had seen him. He was helped by a moderator question on his past exaggerations/inaccuracies regarding his life story that would give the term "softball" a bad name. And by the fact that none of his rivals seemed interested in taking the fight to him on the issue of the inconsistencies of his recounting of the past. Carson was, as usual, very shaky on foreign policy and wasn't much better on regulatory reform. But he did more than enough to keep himself at or near the top of the GOP field. 
 
 * Carly Fiorina: Like Cruz and Rubio, Fiorina proved something Tuesday night that we already knew: She's an able debater. She inserted herself into a variety of discussions — foreign policy, taxes — where she left a positive mark. It also helped that the audience in the room in Milwaukee seemed very much on her side. I still think Fiorina, like Rubio, can come across as too rote at times. 
 
 * Rand Paul: The senator from Kentucky (finally) found ways to get his voice heard in a debate. The problem for him is that he's almost certainly too far down in polling — and in the money chase — for it to matter much. Still, Paul found a platform to voice his unique views on foreign and fiscal policy, and, at this stage of his candidacy, that amounts to a win. 
 
 Losers 
 
 * Donald Trump: Trump, as he has in each of the first four debates, stood center stage in Milwaukee on Tuesday night. But for the two-plus hours that the debate ran, Trump felt ancillary to the conversation. When he did get time to speak, he simply repeated his now-familiar lines — we don't win anymore, I have a great company, etc. — and little else. His answers on foreign policy were not good. His random attack on Fiorina — "why does she keep interrupting everybody?" — earned him boos from the crowd (and helped her). Trump just didn't seem all that interested in being there. It likely won't affect his poll numbers, since nothing seems to. But that doesn't change the fact he was off his game. 
 
 * John Kasich: The Ohio governor came out with a strategy to install himself right in the center of the debate. To do that, he interrupted, cajoled and pouted his way through it. His positions on immigration and on Wall Street banks won't win him any support from the GOP base (he got booed for his Wall Street answer). But it wasn't really about policy. Kasich seemed peevish, short-tempered and anything but presidential. 
 
 * Jeb Bush: Look, the former Florida governor wasn't bad in this debate. In fact, he was far better than the lifeless showing he put in last month. But he wasn't good enough. Jeb's first answer — pledging to repeal all of Obama's executive orders — was forceful and quite good. But as the debate wore on, Bush repeatedly missed chances to jump into conversations — a long back-and-forth involving multiple candidates over taxes jumps to mind — and when he did speak he was somewhat halting and awkward. The Bush people readily acknowledge that debating is not his strong suit. And I readily acknowledge that being a good debater doesn't guarantee victory. But Bush just isn't comfortable on the debate stage — and it shows. 
 
 * Anecdotes: Virtually every candidate took a question about broad fiscal policy and turned it into a heartwarming/heart-wrenching tale of "Jim and Aileen Jones from random city in random state." I know candidates and their staffs believe these anecdotes bolster the idea that they are out meeting regular people and not sitting in the halls of Washington — wherever those are — opining on stuff. But the anecdotes come across more often than not as trite and cliched rather than revealing and powerful. Let's just stop doing it! Okay? Good. It's a deal. 
 
 * Debate format: The Fox Business moderators went out of their way to make clear that they, unlike the unmentioned but ever-present CNBC moderators, would be sticking to substantive economic issues in the debate. Then they went out of their way to praise themselves for doing so. Fine. But the debate was largely lifeless throughout, and the lack of candidate exchanges — whether because of the rules of the debate or a simple unwillingness to engage — meant that many of the answers offered were straight from oft-repeated talking points. I don't think that serves the voters' interests — at all. ||||| The second Republican debate on Wednesday night was a marathon, running for three hours at the Reagan Library in Simi Valley, Calif. Who crossed the line strong and who stumbled along the way? 
 
 WINNERS 
 
 Carly Fiorina 
 
 Fiorina seized her big moment, having moved up from the “B-team” forum to which she was confined at the first debate in Cleveland last month. If expectations were high for Fiorina, she surpassed them with an engaged, passionate performance. A forceful denunciation of Planned Parenthood might have been her standout moment in terms of connecting with the Republican electorate at an emotional level. But she also scored highly throughout, in moments as diverse as discussing foreign policy on one hand and mixing it up with Donald Trump on the other. 
 
 Marco Rubio 
 
 Rubio had a strong night, especially on foreign policy, where he showed real depth. He also more than once laid out positions that were somewhat similar to those of his mentor, former Florida Gov. Jeb Bush, but were delivered with much greater crispness. For example, after Bush meandered through a defense of speaking Spanish on the campaign trail, Rubio argued that it was important for Spanish-speaking voters to hear conservative arguments “directly from me, not from a translator at Univision.” Rubio’s performance at the first debate was also well-received yet made little difference to his polling numbers. Could he get a bump this time? 
 
 Chris Christie 
 
 For all the negative attention Christie has received recently, he has considerable political skills, not least that he is a formidable debater. His best moment came during an exchange between Fiorina and Trump about their respective business careers. The New Jersey governor, forceful as ever, insisted that “for the 55-year-old construction worker out in that audience tonight who doesn't have a job, who can't fund his child's education, I've got to tell you the truth: They could care less about your careers.” No-one knows whether Christie’s performance will change his fortunes with GOP voters who have proven impervious to his charms so far. But he had a good night by any measure. 
 
 Ben Carson 
 
 Carson went into the debate as the closest challenger to Trump in the polls, with the GOP electorate warming up to his low-key, affable style. Carson did not deviate from that path on Wednesday. He didn’t have any single great moment, but it was a proficient performance. And Carson did show that, despite his laid-back style, he can be quick on his feet. After Trump expressed skepticism about vaccines, a smiling Carson shot back, “He’s an OK doctor” — a phrase Trump had used only days before about Carson, an acclaimed former neurosurgeon. 
 
 Ted Cruz 
 
 Cruz appealed to the party faithful on Wednesday with a robust defense of the right to bear arms and a vigorous condemnation of the Iran nuclear deal, among other matters. Cruz also showed that he has as strong a command of TV debating technique as anyone in the field — including looking directly into the camera rather than at audience members. It remains unclear if he can expand his support beyond the most conservative reaches of the GOP, but he had a good night. 
 
 Donald Trump 
 
 Trump was nowhere near as dominant a presence as he was at the first debate, in part because he came under much more sustained attack from his rivals. Trump had some unsteady moments, including one instance when he appeared to suggest he would get himself better informed about threats facing the United States between now and potentially assuming the presidency. He also slid away from his recent personal criticisms of Fiorina by insisting that “she has a beautiful face” — hardly a remark that would win over his own detractors. But he was, on balance, a winner for two reasons. Firstly, for all the punches thrown at him, none put him on the canvas. Secondly, he again got under the skin of Jeb Bush, likely deepening the troubles for the favorite candidate of the GOP establishment. 
 
 MIXED 
 
 John Kasich 
 
 The Ohio governor has been trying to overtake Bush as the establishment choice, and he seemed to be trying to present himself as an electable grown-up. He had his moments but, as one of the lesser-known candidates nationwide, he needs to make a significant impact every time he is in front of a big national audience. He didn’t appear to do so on Wednesday evening. 
 
 Mike Huckabee 
 
 Huckabee has a very different ideological appeal to Kasich, but there are some stylistic similarities: They are both somewhat folksy politicians who can be very effective communicators. But Huckabee suffered from a similar problem to Kasich: Although he had some strong moments — the Kim Davis controversy is almost tailor-made for him — it seems unlikely that he attained any real breakthrough. 
 
 LOSERS 
 
 Scott Walker 
 
 The Wisconsin governor has been falling precipitously in the polls, in part because his performance at the first debate was widely seen as lacking fire and charisma. Walker came out of the gate impressively on Wednesday night with a jab at Trump — “We don’t need an apprentice in the White House” — but he mostly faded after that. His showing wasn’t as bad as it was in Cleveland, but he did nothing that looked likely to turn around his ailing fortunes. 
 
 Rand Paul 
 
 Paul was put on his heels at the start of the night when Trump mocked him for, allegedly, not deserving to be on the stage at all. To be fair to Paul, his performance was not objectively bad. It just did nothing to change the minds of a Republican electorate that seems strongly disinclined to back him. 
 
 Jeb Bush 
 
 The consensus going into Wednesday night’s debate was that Bush needed an animated, commanding performance to erase memories of his hesitant showing in Cleveland. Instead, he delivered more of the same. His remarks on Supreme Court Justice John Roberts, in particular, seemed confused and contradictory. A defensiveness also crept into responses over his brother’s record. And while Bush tried to challenge Trump more assertively than in the first debate, the businessman got the better of most of their exchanges. Bush’s performance, taken in isolation, was not the worst on the stage. But it was far below what might be expected from a man who was the clear GOP front-runner not so long ago. ||||| The Republican National Committee on Friday pulled out of a planned Feb. 26 debate with NBC News amidst a revolt by candidates after Wednesday’s CNBC debate. 
 
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 "While debates are meant to include tough questions and contrast candidates’ visions and policies for the future of America, CNBC’s moderators engaged in a series of 'gotcha' questions, petty and mean-spirited in tone, and designed to embarrass our candidates," RNC Chairman Reince Priebus wrote in a letter to NBC News Chairman Andrew Lack. 
 
 Since CNBC is an NBC Universal property, "We are suspending the partnership with NBC News” for its Feb. 26 debate. 
 
 Priebus’s email panned CNBC for "inaccurate or downright offensive" questions, specifically singling out a question to Donald Trump Donald John TrumpRand's reversal advances Pompeo New allegations could threaten Trump VA pick: reports President Trump puts on the pageantry for Macron’s visit MORE, who was asked whether he was running a "comic book" version of a presidential campaign. 
 
 "What took place Wednesday night was not an attempt to give the American people a greater understanding of our candidates’ policies and ideas. 
 
 Debates can mean big money for networks, which charge premium prices to advertise for the event. CNBC reportedly charged about $250,000 for a 30-second ad during Wednesday night's debate — similar to reported prices for the previous CNN debate. 
 
 The decision is the RNC’s response to the rumbling of complaints that bubbled over during the debate, when Sen. Ted Cruz Rafael (Ted) Edward CruzAfter Dems stood against Pompeo, Senate’s confirmation process needs a revamp Cruz's Dem challenger slams Time piece praising Trump Race for Republican Speaker rare chance to unify party for election MORE (Texas) and other bashed the moderators for political bias and unfair questions. Immediately after the debate, former Florida Gov. Jeb Bush’s campaign manager confronted the network backstage over how little time his candidate received. 
 
 GOP front-runner Donald Trump came out in support of the RNC’s decision Friday afternoon. 
 
 "The campaign supports the RNC’s decision to suspend the debate on February 26th due to the total lack of substance and respect exhibited during Wednesday’s night’s debate," Trump's campaign said in a statement. "We look forward to pursuing alternatives along with the RNC to ensure candidates are given ample opportunity to outline their vision for the future of our country." 
 
 A spokesperson for Ben Carson said the campaign has “no objections to the decision,” but still wants to see changes to the process to ensure the debates are “about informing the public and not about network ratings.” 
 
 Some campaigns are still set to meet this weekend to air their grievances and determine what other steps might be taken to avoid issues in future debates. 
 
 The RNC has tried to take more of a leading role in debates after 2012, slicing the number of debates to about one-third of the contests from that cycle. 
 
 While the editorial decisions, specifically debate questions, are up to the media organizations, it has control over the logistics and ultimately whether the debate gets its blessing. 
 
 But that hasn’t stopped complaints about the criteria in each of the three debates—Fox News chose to lower the qualifications for its undercard debate and CNN expanded the criteria to include Carly Fiorina, both decisions amid criticism. And the pushback from the campaigns on CNBC's debate hasn't relented since late Wednesday night. 
 
 In his letter to NBC, Priebus wrote, "I have tremendous respect for the First Amendment and freedom of the press. However, I also expect the media to host a substantive debate on consequential issues important to Americans. CNBC did not." 
 
 NBC responded to the RNC's decision in an email statement Friday afternoon saying, “This is a disappointing development. However, along with our debate broadcast partners at Telemundo we will work in good faith to resolve this matter with the Republican Party.” 
 
 A source with NBC pointed out that NBC News had no editorial control over the debate. Lack’s corporate bio says that he only oversees NBC News and MSNBC. CNBC is a separate property under the NBC Universal umbrella. 
 
 The RNC still plans to hold a debate on that date that includes National Review, a conservative publication that partnered with NBC for the upcoming debate. 
 
 The decision to pull out of the NBC debate was met with mixed reviews from RNC veterans. 
 
 Jim Nicholson, a former RNC chairman during the 2000 election, applauded Priebus’ decision and told The Hill that the “RNC ought to continue to use their megaphone to try to get these networks and moderators to have the same set of standards.” 
 
 “That’s a pretty big stick because those debates have been very well watched, so the advertising time is very valuable to the networks,” Nicholson said of the threat of pulling out of another debate. 
 
 As far as the candidates, he added, their leverage lies in uniting together if they want to push for substantive changes to future debate criteria. 
 
 “They are the strongest when they act collectively,” he said, adding that Donald Trump and Ben Carson won their demands to have opening and closing statements, as well as a two-hour time limit on the debate, after threatening to pull out of CNBC’s debate. 
 
 That win was short-lived, however, as Priebus' letter notes that the network eschewed the opening statement to instead ask candidates about their weaknesses. 
 
 But former RNC chairman Michael Steele, who has clashed with Priebus in the past, said the move to suspend the partnership with NBC would do nothing ameliorate the frustration candidates have with the debate process as a whole. 
 
 “This doesn’t solve the problem,” Steele said. “The original idea was for the RNC to have more control over the process but now the candidates are already making their move and it’s too late.” 
 
 “I don’t think it’s a bold move,” he added. “They’re trying to appease the candidates who are already pissed off at the process they created. What they’ve got to do is look forward and determine the style of debate they want and who is going to be up there for it, rather than just reacting to what happened with CNBC, which was abhorrent.” ||||| Jeb Bush, who entered Tuesday night’s GOP debate with the most on the line, rose to the occasion and turned in his strongest debate performance to date, but it was Marco Rubio and Ted Cruz who again outshined their rivals. 
 
 While Bush's ability to find his footing on the primetime stage should reassure nervous donors, it’s unlikely to fundamentally change his position in the broader field—a B grade, after all, only brings an F up to a D. 
 
 Story Continued Below 
 
 Rubio and Cruz, now viewed as the two strongest candidates, ceded no ground, exploiting a much softer debate format in Milwaukee and again showcasing their mastery of the facts and ease under the bright lights. 
 
 Donald Trump also roared back to his caustic, combative form. But Ben Carson turned in his shakiest performance yet, struggling with a debate that focused more on substantive policy questions and taking up the least amount of speaking time despite his position in the center of the stage. 
 
 The two-hour debate, marked by a smattering of sharp exchanges but fewer fireworks than the three previous showdowns, is unlikely to dramatically alter the race as it now stands—and the status quo may hold through the end of the year, with the next GOP debate 35 days away and the month of December effectively a dead zone for campaign fundraising. 
 
 Many of the spats that generated heat on stage Tuesday night were familiar ones—illustrative of the broader ideological divisions within the GOP. 
 
 The first focused on immigration, with Trump and Cruz on one side opposite John Kasich and Bush, both desperate for air time given their standing behind the current front-runners and eagerly blasting Trump’s proposal to build a wall along the U.S.-Mexico border and to deport 11 million undocumented immigrants. 
 
 "It’s a silly argument. It’s not an adult argument. We all know you can’t pick them up and ship them back across the border,” said Kasich, paving a path for Bush to follow. 
 
 Trump responded by taking a dig at the Ohio governor and his state's economic recovery. "You’re lucky in Ohio that you struck oil," he said. 
 
 As the tussle escalated and Kasich started talking over him, Trump interjected, saying "I don't have to hear from this man." As Kasich looked to cut in again, Trump suggested he "let Jeb speak." 
 
 Bush followed by mockingly thanking Trump for "allowing me to speak at the debate." He also chided Trump for the mass deportation proposal, calling it "impossible." 
 
 “It’s not embracing American values, and it would tear communities apart,” Bush said about Trump’s plan. “And even having this conversation sends a powerful signal. They’re doing high-fives in the Clinton campaign when they hear this … the way you win the presidency is you have practical plans.” 
 
 Cruz followed with a defense of Trump’s position, asserting “it’s not anti-immigrant,” and landing a repeat of his well-received attack on the media. 
 
 “I understand when the mainstream media covers immigration, it often doesn’t see it as an economic issue, but I can tell you for millions of Americans at home watching this, it is a very personal economic issue,” Cruz said. “I would say the politics of it would be very, very, different if a bunch of lawyers or bankers were crossing the Rio Grande — or if a bunch of people with journalism degrees were coming over and driving down the wages in the press.” 
 
 Rubio, the author of the failed comprehensive immigration reform package that passed the Senate in 2013 but failed in the House for lack of support from grassroots conservatives, stayed out of the fray. 
 
 Rubio did land his own memorable moment when he tangled with Rand Paul, who criticized his proposals to increase military spending. 
 
 “I know that Rand is a committed isolationist,” Rubio said, dismissively. “I know that the world is a safer and a better place when the United States is the strongest country in the world.” 
 
 "Marco, Marco, how is it conservative to add a trillion-dollar expenditure to the federal government?” Paul shot back. “You cannot be a conservative if you’re going to keep promoting new programs that you’re not going to pay for. I want a strong national defense, but I don’t want us to be bankrupt.” 
 
 “You think defending this nation is expensive," Cruz chimed in. "Try not defending it." 
 
 Bush, desperate to improve on his disastrous performance in last month’s third GOP debate in Boulder, Colo., steadied himself with his response on immigration after showing some edginess early on. 
 
 Bush entered Tuesday night’s fourth GOP debate vowing to stop following the moderators’ rules and dead set on making his voice heard. 
 
 But in a major shift from the first three debates that quickly devolved into freewheeling slugfests, the five candidates who got questions before Bush did at the outset of the two-hour debate in Milwaukee were suddenly playing by the rules. 
 
 When Kasich, despite ranking behind Bush in the national polling, offered a lengthy answer to his first question and then threatened to interject after Cruz’s opening statement, an antsy Bush jumped in. 
 
 "I got about four minutes last debate, I'm gonna get my question,” Bush said. 
 
 “I appreciate it, Jeb,” Kasich shot back. “I’m all for you.” 
 
 Bush got his footing as the debate progressed, attacking Trump for his assertion that the U.S. cannot be the world's policemen. "Donald is wrong on this. He is absolutely wrong on this," Bush said. "We are not going to be the world’s policemen but we sure as hell better be the world’s leader." 
 
 “That’s like a board game. That’s like playing Monopoly or something," said Bush, who seemingly meant to refer to the game Risk, not Monopoly. 
 
 Twelve days after his rehearsed attack on Rubio backfired so spectacularly, Bush opted not to attack or engage Rubio at all. 
 
 Carson, who now sits atop some national polls, struggled on a foreign policy question about how he would combat ISIS in the Middle East. 
 
 “We have to say, how do we make them look like losers? And I think the way to make them look like losers, we have to destroy their caliphate,” Carson said, seemingly arguing for ground forces to remove ISIS from Iraq. 
 
 “Take that from them, take that land from them, we could do that fairly easily,” he said. 
 
 Carson also addressed the recent scrutiny of a number of his anecdotal biographical claims, again criticizing the media for portraying him unfairly. 
 
 “The fact of the matter is, we should vet all candidates,” Carson said early in the debate. “What I do have a problem with is being lied about and putting that out there as truth. I don’t even mind that so much if they do that with everybody … when I look at somebody like Hillary Clinton who sits there and tells her daughter and a government official that no this was a terrorist attack and tells everybody else it was a video, where I come from, they call that a lie. 
 
 “I think that’s very different from somebody misinterpreting when I said I was offered a scholarship to West Point,” he continued. “People who know me know that I’m a honest person.” ||||| Cruz was tough and canny—no surprise there. He went the full-Gingrich in his assault on CNBC’s ridiculous moderators. He did a better job explaining Social Security reform than Chris Christie, even (which is no mean feat). And managed to look downright personable compared with John Harwood, whose incompetence was matched only by his unpleasantness. If you’re a conservative voter looking for someone who is going to fight for your values, Cruz must have looked awfully attractive. 
 
 Rubio ended Jeb Bush’s campaign with the kind of body shot that buckles your knees. That’s on Bush, who never should have come after Rubio in that spot for a host of strategic and tactical reasons. But what should scare Hillary Clinton is how effortless Rubio is even with throwaway lines, like “I’m against anything that’s bad for my mother.�? Most people have no idea how fearsome raw political talent can be. Clinton does know because she’s seen it up close. She sleeps next to it for a contractually-obligated 18 nights per year. 
 
 Tonight’s debate showed that the GOP field is smaller than it looks. Technically, there are still fourteen people running, but the winnowing is far along. We probably have a final six and possibly a final four. 
 
 Then there was Trump. Over the last few weeks, Trump has gotten better on the stump. Well, don’t look now, but he’s getting better at debates, too. Trump was reasonably disciplined. He kept his agro to a medium-high level. And his situational awareness is getting keener, too. Note how he backed John Kasich into such a bad corner on Lehman Brothers that he protested, “I was a banker, and I was proud of it!�? When that’s your answer, you’ve lost the exchange. Even at a Republican debate. 
 
 And Trump had a hammer close: “Our country doesn’t win anymore. We used to win. We don’t anymore.�? I remain convinced that this line (along with his hardliner on immigration) is the core of Trump’s appeal. But he didn’t just restate this theme in his closing argument. He used it to: (1) beat up CNBC; and (2) argue that his man-handling of these media twits is an example of what he’ll do as president. It was brilliant political theater. 
 
 Those were your winners. You also saw tonight several campaigns which are over, even if the candidates don’t know it yet. Kasich was less likable than Rand Paul. Rand Paul was mostly invisible, and petulant when he was visible. Mike Huckabee wasn’t visible enough, except when he was doing his populist defense of Medicare and Social Security. But the effectiveness of this spot was diminished by Cruz’s excellent response, which is what people are apt to remember. There just isn’t enough space for him to make an impact by dint of personality in a field with a bunch of other strong and attractive personalities. And as for Bush? Jeb’s dead, baby. Jeb’s dead. 
 
 That leaves us with Chris Christie, Carly Fiorina, and Ben Carson, who, by the way, is actually leading the field in some polls. 
 
 Christie was as impressive tonight as he could be, given his position. He had a great opening. His interjection on regulating fantasy football was tremendous. The “Even in New Jersey what you’re doing is called rude�? line to Harwood just killed. If the establishment had jumped on Christie early, instead of being scared off by the GW bridge scandal and going for Bush . . . well, this race would probably be different. But they didn’t. That said, we’ll keep Christie in our final grouping because he’s so talented that he’s always going to have a puncher’s chance. 
 
 Fiorina had a solid debate, but wasn’t the run-away winner she’d been in the first two debates. If her numbers couldn’t hold when she was the class of the field, I doubt they’ll move much when she’s merely on the high-side of the average. It looks more and more like Fiorina isn’t running to win the nomination. 
 
 And what to do about Carson? Gentle Ben was fine—great in some moments; pedestrian in others. I don’t think many people in the media fully grasp the passion for Carson, but that doesn’t make it any less real. And if you look at the history of Iowa, and Carson’s numbers now, it’s not hard to imagine him doing very well there. 
 
 So there’s your final six: Trump, Carson, Rubio, Cruz, and maybe—just maybe—Fiorina and Christie. ||||| Washington (CNN) Republican presidential candidates sought to cement -- or improve -- their standings in a debate Tuesday night that comes less than two months before the first votes of the election season are cast. 
 
 The CNN debate in Las Vegas marked the first time the White House hopefuls shared a stage since terror attacks in Paris and San Bernardino, California. They flashed their foreign policy credentials and targeted each others' weaknesses in the debate that lasted more than two hours and focused exclusively on foreign policy and national security. 
 
 The result of the showdown: Some winners, and some losers. 
 
 Winners 
 
 Jeb Bush 
 
 The former Florida governor walked onto the CNN debate stage on Tuesday facing a make-or-break moment for his struggling campaign. 
 
 Polling at about 3% nationally, pundits had low expectations for Bush. But he was able to make the most of the moment and his performance will likely reassure skittish donors and supporters who have doubted him. 
 
 Appearing confident, Bush repeatedly engaged front-runner Donald Trump and at times flustered the real estate mogul. Unlike previous debates where he has backed off, Bush didn't relent in the face of Trump's return fire. 
 
 JUST WATCHED Gov. Jeb Bush: Trump's rhetoric is 'dog whistle talk' Replay More Videos ... MUST WATCH Gov. Jeb Bush: Trump's rhetoric is 'dog whistle talk' 02:40 
 
 "If you think this is tough and you're not being treated fairly, imagine what it's going to be like dealing with Putin or dealing with President Xi or dealing with the Islamic terrorism that exists," Bush said over Trump's persistent interruptions. 
 
 CNN political commentator Michael Smerconish said after the debate that Bush "turned in a strong performance" with his ability to repeatedly needle Trump. 
 
 "Jeb had a good night," he said. 
 
 Ted Cruz 
 
 The tea party favorite avoided a cage match with front-runner Donald Trump in favor of a sparring match with Rubio. 
 
 Cruz and Trump have largely avoided skirmishes on the campaign trail but that ended in recent days as the Texas senator's standing improves in Iowa. 
 
 Former Mitt Romney aide and current CNN political commentator Kevin Madden said Cruz's strategy of avoiding confrontation on the debate stage was effective. 
 
 "I think the strategy Cruz has is working, bear hugging Donald Trump. I think Donald Trump does not feel antagonized," he said. 
 
 While Cruz didn't give viewers anything like the fiery and memorable soundbites his supporters savored in the last debate, the Texas senator gave a strong performance sure to please his base. And by taking aim at -- and holding his ground against -- Rubio, Cruz did nothing to stall his burgeoning momentum. 
 
 Marco Rubio 
 
 Sen. Marco Rubio delivered a front-runner's performance, as he parried blows from all sides in the crowded field. 
 
 Rubio worked to stay above the fray of candidates, focusing on showing off his in-depth understanding of foreign policy and deflecting the attacks his competitors hurled his way. The Florida senator, though engaged in heated exchanges with Cruz and Rand Paul at times, mostly sought to flex his hawkish national security positions rather than attack his competitors. 
 
 JUST WATCHED Marco Rubio attacks Ted Cruz's voting record Replay More Videos ... MUST WATCH Marco Rubio attacks Ted Cruz's voting record 02:38 
 
 When prompted to address Trump's proposal to bar foreign Muslims from entering the U.S. -- which Rubio opposes -- or to address his recent criticism of Cruz, Rubio didn't bite. Instead, the Florida senator used the opportunity to speak at length about foreign policy concerns and his own proposals -- or to attacking President Barack Obama's administration. 
 
 Donald Trump 
 
 As the real estate mogul has done in recent debates, Donald Trump offered a measured performance stylistically different from the fiery stump speeches he delivers at rallies to supporters. And the typically confrontational businessman largely avoided tangling with his fellow contenders. 
 
 It was a safe performance for Trump, but it's one that certainly won't deter his supporters and won't do anything to hurt his front-runner status. 
 
 JUST WATCHED Donald Trump commits to the Republican Party Replay More Videos ... MUST WATCH Donald Trump commits to the Republican Party 01:08 
 
 CNN political commentator David Axelrod, a former top Obama adviser, said that while Trump didn't meet the bar on facts and "linear thinking," he was "in character." 
 
 "I think he probably did what he needed to do," Axelrod said, adding that it didn't hurt that few of the candidates to Trump's right and left were "eager to tangle" with the front-runner. 
 
 Chris Christie 
 
 New Jersey Gov. Chris Christie's goal on Tuesday was to try and further his recent rise in stock in the early primary state of New Hampshire, where talk of national security has boosted the former federal prosecutor. 
 
 Christie managed to poke at the three senators in the race by lamenting the tit-for-tat debates Cruz, Rubio and Paul engaged in. The governor continued to play to his executive experience and his prosecutions of terrorism cases as a U.S. attorney. 
 
 In one of his strongest moments, Christie slammed the senators on stage as "people who've never had to make a consequential decision in an executive position" and proclaimed that voters were looking for "a president who actually knows what they're doing." 
 
 CNN political commentator Jeffrey Lord, a Trump supporter, noted that like Trump, Christie "was delivering a message" on stage rather than getting too "in the weeds" on policy. 
 
 Losers 
 
 Ben Carson 
 
 Ben Carson said it himself on Tuesday heading into the last debate of the year: He needed to prove his national security credentials to reassure voters fleeing his campaign amid rising concerns over terrorism. 
 
 But the retired neurosurgeon faltered on that front -- offering little in the way of assuaging those concerns, which are believed to have contributed to Carson's fall from his position near the top of the polls in Iowa and nationally. 
 
 Instead, Carson offered vague and meandering responses to specific foreign policy questions, complained about the time allotted to him and declined when asked whether he sided with Cruz or Rubio in the debate over National Security Agency data collection. 
 
 Carly Fiorina 
 
 Carly Fiorina still looked and sounded like a top debater on stage Tuesday night, but a closer look shows that the former Hewlett-Packard CEO is offering little to voters that they haven't already heard. 
 
 In short, Fiorina's shtick is getting old. 
 
 And several of Fiorina's attempts to elbow her way into the debate as other candidates were speaking -- a tactic that has worked for her in the past -- didn't help her during this performance. 
 
 Her strongest moments, though, came when she touted her experience as a tech executive as a way to highlight the need for the private sector to boost the federal government's counter-terrorism efforts. 
 
 John Kasich 
 
 Kasich faced a similar problem as Fiorina -- he didn't offer anything new that would jumpstart his candidacy. 
 
 Kasich tried his best once again to play the role of the adult in the room, calling out Trump for unserious proposals and questioning other candidates' assessment of the situation in Syria, for example. 
 
 But Kasich failed to snag himself a moment. 
 
 Rand Paul 
 
 The libertarian senator from Kentucky showed he was in a fighting mood from the outset: jabbing at Trump and Rubio in his opening statement 
 
 Unfortunately for Paul, nobody wanted to tangle with him. 
 
 JUST WATCHED Rand Paul questions Donald Trump's candidacy Replay More Videos ... MUST WATCH Rand Paul questions Donald Trump's candidacy 01:31 
 
 Even Trump -- who rarely resists an opportunity to needle his competitors -- didn't take the bait when Paul hit him at several points in the debate. 
 
 "Marco can't have it both ways," Paul said, attacking Rubio on immigration. "He wants to be this I'm great and strong on national defense, but he's the weakest of all the candidates on immigration." 
 
 But Rubio didn't hit back, simply thanking Paul for giving him another 30 seconds of talking time -- afforded to any candidate called out by one of his opponents -- and using it to lay out his position. 
 
 While Paul made his case against the neoconservative ideology coursing through the arteries of the Republican Party, he was effectively shut out by the overwhelming opposition to his foreign policy views present on stage. 
 
 GOP prime-time verbal attacks: ||||| The final Republican presidential debate of 2015 brought heated clashes between several major candidates in Las Vegas on Tuesday night, when national front-runner Donald Trump Donald TrumpTrump says he will reevaluate 'dumb deal' to resettle refugees from Australia Homeland Security chief hopes to complete border wall in two years Longtime doctor: Trump takes drug to promote hair growth MORE tangled with a newly assertive Jeb Bush, and Marco Rubio Marco RubioSenate confirms Tillerson as secretary of State Trump's regulatory rollback a relief to small business Bannon’s power puts Republicans on edge MORE and Ted Cruz Ted CruzLiberal groups fundraise off Supreme Court fight Franken slams Cruz for ‘trying to impugn’ his record The Hill's 12:30 Report MORE repeatedly jabbed at each other. 
 
 Who won and who was left licking their wounds with only seven weeks — and one more debate — left before the Iowa caucuses? 
 
 WINNERS 
 
 Former Florida Gov. Jeb Bush 
 
 Bush had by far his strongest performance in any debate to date. The former Florida governor, whose last election campaign was in 2002, had looked rusty and hesitant in all his previous outings. On Tuesday night he made a far crisper and more assertive showing. 
 
 Bush delivered the most memorable line of the debate’s early stages when he said Trump was “a chaos candidate. And he’d be a chaos president.” In a later exchange, he told the businessman, “You’re not going to be able to insult your way to the presidency,” a phrase met with applause from the audience at The Venetian casino hotel. 
 
 ADVERTISEMENT 
 
 There were important caveats to Bush’s performance. He didn’t win every tussle. The awkward, fumbling Bush on display in the first four debates suddenly reappeared when it was time for a closing statement. And the biggest question is whether a good debate can really help a candidate who languishes at just 4 percent national support, according to the RealClearPolitics polling average. 
 
 Still, Bush's supporters can take heart. The candidate they’ve been expecting for months finally showed up on Tuesday evening. 
 
 Sens. Ted Cruz (Texas) and Marco Rubio (Florida) 
 
 The two senators have been on the rise in recent polls — Cruz more dramatically than Rubio — and each man seemed to keep his momentum going. The two punched and counter-punched throughout the night on subjects including government surveillance, military spending and immigration. 
 
 The exchanges were often sharp: Cruz repeatedly accused Rubio of sowing confusion and even invoked the name of left-wing organizer Saul Alinsky — a much-hated figure among conservatives — when describing the Floridian’s tactics. But Rubio stayed on offense for the most part, and Cruz did himself no favors by at times attempting to talk roughshod over rivals and moderators. 
 
 The senators ultimately fought to a draw, and the fact that their jousting took up so much airtime underlined their status as the candidates on the rise, right behind Trump. 
 
 New Jersey Gov. Chris Christie 
 
 Christie, who was once written off in this year’s race, is now a serious contender in New Hampshire, at least. His impressive performances in debates have helped fuel his resurgence. Tuesday was not Christie’s best night at the podium, but he acquitted himself well, especially when he contrasted his executive experience as a governor with the work of the three senators onstage, whom he disparaged as talkers rather than people of action. 
 
 On the subject of guarding against terrorism while also not infringing civil liberties, Christie exhorted the moderators to "talk about how we do this, not about which bill ... these guys like more. The American people don't care about that.” 
 
 MIXED 
 
 Businessman Donald Trump 
 
 Trump’s instincts for how to make news are unerring, and he proved that again with a declaration in the debate’s closing stages that he would not make a third-party run for the White House if he failed to secure the GOP nomination. That alone will ensure that the national front-runner wins his share of headlines in the aftermath. 
 
 But it was otherwise an indifferent night for Trump, who encountered more audible hostility from the crowd in Las Vegas than he has during previous bouts. 
 
 Trump’s disdain for details has long disconcerted political professionals, and it manifested itself again in a confusing answer about whether he would seek to restrict Internet access as part of the battle against radical Islamic militants. But Trump’s “broad strokes” approach has not harmed him so far, and there is no reason to assume it will do so now. 
 
 Sen. Rand Paul Rand PaulTiny island nation standing up to 'hare-brained' tax haven law Overnight Healthcare: GOP talk shifts from replacing ObamaCare to repairing it | HHS pick advances after rules change Freedom Caucus meets with senators on ObamaCare replacement MORE (R-Ky.) 
 
 Paul only made the main stage for this debate by the skin of his teeth, but he made adequate use of the opportunity. 
 
 The moderators’ focus on foreign policy and national security helped Paul in one sense: He got the chance to expound on the libertarian-leaning beliefs that are the bedrock of his politics and to express his skepticism about military action. 
 
 “We have to have a more realistic foreign policy and not a utopian one where we say, ‘Oh, we're going to spread freedom and democracy, and everybody in the Middle East is going to love us,’ ” he said in the late stages of the debate. “They are not going to love us.” 
 
 The problem for Paul is twofold. First, however polished his arguments on these issues, there is no evidence at all that a plurality of Republican voters agree with him. Secondly, he is likely just too far behind — he averages around 2 percent support nationally, according to RealClearPolitics — for even a positive showing to make much difference. 
 
 LOSERS 
 
 Retired neurosurgeon Ben Carson 
 
 The halcyon days of Carson’s presidential campaign look as if they could be over. His poll ratings have been dropping precipitously in recent weeks, since terrorist attacks in Paris and San Bernardino, Calif., raised questions about his grasp of foreign policy. 
 
 Carson’s debate style has always been unorthodox: soft-spoken and affable to his supporters but vague and meandering to his critics. That was acceptable when he was soaring in the polls, but it’s hard to see how it can possibly turn around his recent decline. 
 
 Ohio Gov. John Kasich and businesswoman Carly Fiorina 
 
 Neither Kasich nor Fiorina had any real flubs. But they both needed something extraordinary to vault into serious contention for the nomination. They didn’t get it. Both candidates were marginal figures for long stretches of the two-hour debate.
– Compared to last month's CNBC debate, Tuesday night's GOP debate in Milwaukee was long on policy and short on "gotcha" questions and clashes between candidates and moderators, though analysts say the scorecard isn't that different from last time around, with front-runners Donald Trump and Ben Carson both failing to shine. A look around at the chatter: Winners. Ted Cruz and Marco Rubio were widely seen as the night's standouts, with Politico describing them as "the two strongest candidates" after "showcasing their mastery of the facts and ease under the bright lights." Chris Cillizza at the Washington Post deems Cruz, after his attacks on DC's "crony culture, to now be the "outsider" candidate most likely to succeed. Honorable mentions. Carly Fiorina and Rand Paul both had praiseworthy moments, with Fiorina once again demonstrating a strong command of the issues and impressive debating skills. Paul managed to get his message on fiscal policy across, and, "at this stage of his candidacy, that amounts to a win," per the Post. Carson's performance was seen as middling, with policy answers lacking in substance, though he did ably deflect a question about the recent controversies over his life story. Jeb Bush. He needed a good night after a dismal performance last month, and opinions are split on whether he delivered. It "was Bush's best performance in any of the debates so far," according to the Hill—but "unfortunately for him, that's a rather low bar." He was more assertive than in previous debates, though it's "uncertain" whether that will be enough to give his campaign much of a boost, notes a New York Times assessment. Still, it adds that "he no longer seemed as desperate to be somewhere else," while a Politico analysis has a "Bush stops the bleeding" headline and theme. Losers. John Kasich was more of a presence in this debate, but it was not a presence many people liked, with the National Review calling him "angry, condescending, and unprincipled" and likening him to "the drunk, obnoxious uncle everyone wishes hadn't accepted the invitation to Thanksgiving dinner." Trump's performance was seen as his weakest yet, and Politico says he "committed perhaps the biggest gaffe of the night" by suggesting wages in America are too high. Fox Business Network. Unlike CNBC's widely criticized debate, Fox's debate was seen as "fair and balanced," with candidates receiving a roughly equal amount of speaking time, ranging from 13 minutes 35 seconds for Cruz to 9 minutes 22 seconds for Carson, according to Politico. "And that @CNBC is how you run a debate," tweeted RNC chairman Reince Priebus. Click for some of the biggest moments and best lines from the debate.