Republican presidential nominee Mitt Romney pauses while speaking at a campaign rally at the Patriot Center at George Mason University in Fairfax, Va., on Monday. Charles Dharapak/AP hide caption

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A new NPR poll shows the outcome of the Nov. 6 election is too close to call. Mitt Romney leads President Obama nationwide; Obama leads Romney in key battleground states. Both leads are within the poll'€™s margin of error. Pablo Martinez Monsivais/AP hide caption

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Mitt Romney shakes hands with President Obama after their final debate Monday in Boca Raton, Fla. Eric Gay/AP hide caption

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Democratic presidential candidate George McGovern talks about the bombs being used in Vietnam at a $250-a-person fundraising dinner in Los Angeles on Sept. 27, 1972. AP hide caption

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President Obama and former Massachusetts Gov. Mitt Romney participate in the second presidential debate at Hofstra University in Hempstead, N.Y., on Tuesday. Charles Dharapak/AP hide caption

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Early voting has begun in the battleground states of Ohio, Virginia and Iowa. Voting booths were set up for early voting Thursday at the Black Hawk County Courthouse in Waterloo, Iowa. Ahead of Wednesday's first presidential debate, an NPR poll finds President Obama with a 7-point lead nationally, but his GOP challenger, Mitt Romney, is within striking distance. Scott Olson/Getty Images hide caption

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What does your vision of America look like? Loud Red Creative/iStockphoto.com hide caption

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Los Angeles Mayor and Democratic Convention Chairman Antonio Villaraigosa calls for a vote to amend the platform Wednesday at the Democratic National Convention in Charlotte, N.C. Charles Dharapak/AP hide caption

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