This TPM article is chock full of information I did not know.
Polls Suggest Undecideds Won’t Help Romney (If They Show Up)
The latest WSJ/NBC national poll puts Obama up over Romney by the narrowest margin, 48 percent to 47 percent. But it’s the poll’s breakdown of respondents who are either undecided or still willing to consider switching that stands out. According to NBC, the 9 percent of voters who fit the bill are overwhelmingly warmer to Obama. They approve of his performance by a 48-41 margin and like him personally by a 46-29 margin, both better than his national averages. Romney, by contrast, fares much worse with a 22-46 favorability rating.
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The Obama campaign has been making the opposing case to Romney’s for months, arguing that the available data on undecided voters suggests they’re less friendly towards Romney even if they’re aren’t fans of Obama. Based on their current polling, campaign officials are expecting something resembling a 50-50 split.
Looking at the latest numbers, there’s little indication that undecideds are turning to Romney this week and at least some signs that point the other way. Pew’s final election poll used a regression model to game out where the remaining undecideds were headed based on their demographics, ideological leanings, and feelings towards the candidates. The result was an even split: Obama led 48-45 without the model, 50-47 with it.