First Thoughts: Obama's Midwest firewall? Has Obama built a Midwest firewall?... New NBC/WSJ/Marist polls: Obama leads Romney 51%-45% in Wisconsin and 51%-43% in Iowa... Romney camp insists the Iowa race is MUCH closer than our poll suggests... Why the campaigns are pushing back on polls they don't like: Both sides want to look like winners with 18 days to go... AP raises more questions on Libya... Obama stumps in Fairfax, VA, while Romney hits Daytona Beach, FL with Paul Ryan... And "Meet the Press" has Axelrod, Portman, and Rubio. Obama's Midwest firewall? Is this campaign about one region and one region alone? How the Midwest goes, so goes this election? Now the question is whether Mitt Romney and Republicans have made inroads in the Midwestern battlegrounds or not. They say they have. But our new NBC/WSJ/Marist polls of Iowa and Wisconsin, plus our survey last week of Ohio, suggest that President Obama has built a firewall in the Midwest, even after Romney's momentum from that first presidential debate. In Wisconsin, Obama leads Romney by six points among likely voters, 51%-45%, which is virtually unchanged from the margin last month. In Iowa, Obama is up by eight points, 51%-43%, which also is nearly identical to where it was in September. And as we revealed last week, Obama was ahead in Ohio, 51%-45%. What's significant here: If Obama wins all three states, he surpasses 270 electoral votes. But if Romney is able to pick off one of them, that widens the GOP's path to 270 and narrows the Democratic one. Romney camp: The Iowa race is much closer: The Romney campaign insists, however, that the contest is MUCH closer in Iowa than our NBC/WSJ/Marist poll shows. The X-factor here may very well be early voting. Per our poll, 34% of likely voters say they have already cast their ballots, and the president is winning those people, 67%-32%. Another 11% say they are planning to vote early, and Obama is up with them, 55%-39%. On the other hand, Election Day voters have Romney ahead, 54%-39%. But Republicans have pointed out that 285,000 early and absentee ballots have been received in Iowa, which is about 19% of the 2008 electorate in the state -- so less than the 34% in our poll. But an overall total 463,000 absentee ballots have been REQUESTED in the state, and that comes to 30% of the 2008 electorate, which is much closer to that 34%. So what's going on here? Are likely-voter models overstating those who have voted early? Are Democrats just more apt to say they've voted early (even if they haven't), because Obama is asking them to do so? Are these requested absentee ballots already in the mail but haven't been received by the Iowa secretary of state? These are all fair questions to ask. And, yes, it makes polling in these heavy early-voting states much harder. Jim Young / Reuters Republican presidential nominee Mitt Romney greets supporters at a campaign rally at Lake Erie College in Painesville, Ohio in this file photo. The importance of looking like a winner: Given the reaction from Romney World about our Iowa survey, and also given the Obama campaign's reaction to the recent USA Today/Gallup poll, it's important to make a broader point: Both sides want to look like a winner with 18 days to go until Election Day. The fact is, Republicans have very little margin for error in the Midwest, and need all of their voters to turn out. And the same is true for Democrats in what promises to be a close election, especially say in a place like Florida or Virginia. No campaign wants to lose a single vote from someone who might say, "It looks like my side is going to lose, so why vote?" And that's probably why they're aggressively pushing back on polls that appear to poke holes in the narratives they're telling -- that Romney is gaining ground in the Midwest, and that Obama maintains a big gender-gap advantage with women. The bottom line: The Democrats have NO margin for enthusiasm error in Florida and Virginia, and Republicans have NO margin for enthusiasm error in Wisconsin, Iowa, and Ohio. More questions on Libya: Three days until the final Obama-vs.-Romney debate -- on the topic of foreign policy -- don't be surprised if this story gets raised. The AP: "The CIA station chief in Libya reported to Washington within 24 hours of last month's deadly attack on the U.S. Consulate that there was evidence it was carried out by militants, not a spontaneous mob upset about an American-made video ridiculing Islam's Prophet Muhammad, U.S. officials have told The Associated Press. It is unclear who, if anyone, saw the cable outside the CIA at that point and how high up in the agency the information went. And this is the central question: Did the intelligence community not quickly share that information with the Obama administration? And if that's the case, why not? Or did the administration get the intel quickly -- but chose to sit on it until it had no choice (including sending out Susan Rice to relay outdated intelligence on the Sunday shows)? On the trail: Obama holds a rally at George Mason University in Fairfax, VA at 11:45 am ET... Romney and Ryan stump in Daytona Beach, FL at 8:30 pm ET, and Ryan hits Tampa before that... Biden is in Sun City Center, FL... First Lady Michelle Obama and Bill Clinton hold separate events in Wisconsin... John McCain and Kelly Ayotte campaign for Romney in New Hampshire... And Chris Christie holds a rally in Richmond, VA. On "Meet" this Sunday: NBC's David Gregory interviews David Axelrod, Ohio Sen. Rob Portman, and Florida Sen. Marco Rubio. Countdown to 3rd and final presidential debate: 3 days Countdown to Election Day: 18 days