President Obama pauses for a photo with supporters after arriving for a campaign stop in Manchester, N.H., on Thursday. Winslow Townson/AP hide caption

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A blimp with a message in support of Republican presidential nominee Mitt Romney flies over Plantation, Fla., on Sunday. Saul Loeb/AFP/Getty Images hide caption

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Aides tack up an American flag to a barn at the James Koch farm in Van Meter, Iowa, on Oct. 9, ahead of Republican presidential candidate Mitt Romney's arrival for a rally. Jim Watson/AFP/Getty Images hide caption

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Costumed demonstrators on Oct. 3 in Denver, before the first presidential debate. Doug Pensinger/Getty Images hide caption

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A volunteer hands out buttons before first lady Michelle Obama speaks at a Hispanic caucus on Sept. 5 in Charlotte, N.C. David Goldman/AP hide caption

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An advertisement for then-presidential candidate Barack Obama appeared in the Xbox 360 Live version of the video game Need for Speed: Carbon in 2008. Again this year, Obama is advertising in video games. AP/Electronic Arts Inc. via Obama campaign hide caption

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President Obama and Mitt Romney campaign in August: Obama in Leesburg, Va.; Romney in Waukesha, Wis. AP hide caption

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Pamela Anderson performs with Tristan MacManus on Dancing With the Stars: All-Stars. Anderson was the first contestant eliminated on the show this season. Adam Taylor/ABC hide caption

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Ohio State Treasurer Josh Mandel, the Republican challenging incumbent Sen. Sherrod Brown, D-Ohio, speaks at a campaign rally on Sept. 1 in Cincinnati. Al Behrman/AP hide caption

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Americans for Prosperity brought its "Failing Agenda" bus tour to suburban cities in Colorado's heavily populated Front Range. Kirk Siegler/KUNC hide caption

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President Obama's campaign bus is parked in Missouri Valley, Iowa, on Aug. 13. On Friday, Obama was scheduled to return to the swing state for more campaigning. Jim Watson/AFP/Getty Images hide caption

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