Vice President Biden and President Obama wave to the delegates Thursday night at the conclusion of the Democratic National Convention in Charlotte, N.C. Robyn Beck /AFP/Getty Images hide caption

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Former President Bill Clinton at the Democratic National Convention in Charlotte, N.C., Wednesday night. Mladen Antonov /AFP/Getty Images hide caption

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The scene Tuesday night at the Democratic National Convention in Charlotte, N.C. Mladen Antonov /AFP/Getty Images hide caption

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Republican presidential nominee Mitt Romney on Thursday at the Republican National Convention in Tampa. Spencer Platt/Getty Images hide caption

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Weeds were already growing in the parking lot outside the GM assembly plant in Janesville, Wis., on May 4, 2009. Scott Olson/Getty Images hide caption

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