"The latest USA Today/Gallup polling shows a close race in the 2012 swing states, with Obama leading Romney, 47 percent to 45 percent, amid an intensifying presidential air war:
In a new USA TODAY/Gallup Poll of swing states, an overwhelming majority of voters remember seeing campaign ads over the past month; most voters in other states say they haven't. In the battlegrounds, one in 12 say the commercials have changed their minds about President Obama or Republican Mitt Romney — a difference on the margins, but one that could prove crucial in a close race.
At this point, Obama is the clear winner in the ad wars. Among swing-state voters who say the ads have changed their minds about a candidate, rather than just confirmed what they already thought, 76% now support the president, vs. 16% favoring Romney. …
To be sure, Obama's ads have done more to win back Democrats than to win over independents or Republicans: Thirteen percent of Democrats say their minds have been changed by ads, compared with 9% of independents and 3% of Republicans.
A month ago, the race was Obama 48-Romney 44 in the same poll. It's hard to say whether the 2-point difference is meaningful, or just statistical variation. Either way, a ton of money is being spent -- by Obama and GOP outside groups, in particular -- without any major shift in the race. Obama's ads may have held back Romney's momentum, but we're still looking at a close race with no silver-bullet ads on either side."