GOP presidential debate: Winners and Losers The 20th (and maybe final) debate of the Republican presidential battle is in the books, which means it's time to look at who had a good night - and who didn't. Losers: Rick Santorum: The former Pennsylvania senator came into Wednesday night's debate riding high, having emerged from a long period as an also ran to rise to the top of national polls. Santorum has been great in many of the debates in the past, getting clean shots at his rivals and casting himself as the most conservative candidate in a race defined by primary voters looking for an authentic conservative. So it's something of a shock how badly he stumbled Wednesday night. Santorum was on defense all evening, bumbling and stumbling when pressed on his decision to support former Pennsylvania Sen. Arlen Specter, the Title X law of 1970 that aims to provide contraceptives to those who cannot afford them and the No Child Left Behind, the 2001 law giving a greater role for the federal government in education policy. On NCLB, he essentially said that he voted against his conscience on order to help his party since the law was a major priority for President George W. Bush. Santorum called the decision as taking "one for the team." It was a terrible strategy for a candidate whose entire campaign is built on his pure conservatism in opposition to Romney, and it made Santorum look like a hack Washington insider more interested in playing games than doing what is right. Polls show Santorum in a tight race with Romney in Michigan, which holds its primary next Tuesday; a Romney loss there would be devastating and position Santorum as the frontrunner for the nomination. Tonight's debate was a chance for Santorum to show he was rising to the occasion, to showcase a vision and clarity of message that made him plausible as a successful general election candidate. Outside of a couple good moments, he failed. Debate viewers: The first half of the two-hour debate got bogged down an impossible-to-follow battle over earmarks and how they work; it was both boring and relatively trivial, in light of the relatively small role earmarks play in the federal budget. Most of the candidates dodged a question on whether they support contraception and got away with it; they were asked, pointlessly, to describe themselves in one word (for the record, Ron Paul said "consistent," Santorum "courage," Romney "resolute" and Newt Gingrich "cheerful"); and they didn't get asked about immigration until the second hour, despite the fact that the debate was in Arizona, which (like Michigan) holds its primary next Tuesday. In addition, frankly, it was just a pretty boring faceoff; the fireworks were muted, and there was no YouTube moment like Rick Perry's infamous "oops." Though Perry was in the audience, prompting one Twitter user to quip that he had just gotten through his first gaffe-free debate. Perhaps it was because they were all seated, but the event too often resembled a panel discussion during which half the audience nods off. Winners: Mitt Romney: Romney wasn't amazing Wednesday night, but any loss for Santorum - who is now his chief roadblock to winning the nomination - is a win for him. Though he sometimes appeared prickly, Romney had done enough homework to defend himself and land some punches along the way. One example: Romney's strong defense of his opposition to a government bailout of Detroit despite his support for a Wall Street bailout, which he topped off by noting that Santorum had backed airline and steel industry bailouts. It wasn't a clear cut debate victory like the one Romney had over Gingrich after Gingrich win the South Carolina, but it might have been good enough to move the needle in his direction just enough to put him over the top on Tuesday. Newt Gingrich: Gingrich also wasn't at his best on Wednesday, but he got the job done. Gingrich managed to get in an attack at the "elite media" for what he said was not challenging President Obama for supporting "infanticide" - unsurprisingly a crowd pleaser, if not entirely accurate - and looked like the voice of reason after the endless earmarks battle, speaking clearly after Romney and Santorum babbled on interminably. That said, there were moments that make clear why polls show Gingrich to be one of the most popular politicians in the country; he looked downright condescending at times - at one point seeming to mouth "nice try" to Romney with a grin on his face - and also went over the top with rhetoric like "As long as you're America's enemy you're safe. The only time you have something to worry about if you're an American enemy. I guess nobody told Osama bin Laden. Ron Paul: Paul came into the debate looking like an also ran - he's the only candidate yet to win a state - and while he's not going to get a huge boost out of his performance, he had some strong moments. He was the only candidate to offer a straight answer on contraception, saying pills "can't be blamed for the immorality of our society," and he didn't try to explain away his attacks on Santorum, instead unapologetically embracing the rhetoric in his ads. Paul also got in perhaps the best shot on Santorum of the night, seizing on Santorum's claim that politics is a "team sport" to argue that a politician's allegiance should be to their country and Constitution, not their party. Barack Obama: None of the Republican candidates looked particularly presidential Wednesday evening; there was too much squabbling, and not enough of the sort of clear-eyed rhetoric and articulation of solutions that wins elections. In a number of the other debates, Romney was able to rise above the fray while his rivals battled it out, looking presidential in the process; with Santorum up nationally and Michigan around the corner, he couldn't do that Wednesday night, and he suffered as a result. It's good news for a president who is able to keep sharpening his message as his potential rivals weaken each other ahead of the bigger fight in November. More from the debate: Santorum fights charges he's a "fake" conservative Republican candidates spar over congressional spending GOP candidates blast Obama for birth control ruling Republican candidates condemn auto bailout