President Obama greets audience members Saturday after speaking at a campaign event at Mentor High School in Mentor, Ohio, before traveling to Milwaukee for another campaign event. Carolyn Kaster/AP hide caption

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President Obama holds a copy of "The New Economic Patriotism: A Plan for Jobs & Middle-Class Security," which outlines some of his agenda for a second term, during a rally in Richmond, Va., on Thursday. Chip Somodevilla/Getty Images hide caption

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Broward County canvassing board member Judge Robert Rosenberg examines a disputed ballot Nov. 24, 2000, in Fort Lauderdale, Fla. Wilfredo Lee/AP hide caption

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President Obama speaks to supporters last month during a campaign stop in Las Vegas. Isaac Brekken/Getty Images hide caption

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A boy examines CSPAN's 2012 presidential race electoral map at the American Presidential Experience exhibit last month in Charlotte, N.C. Brendan Smialowski/AFP/Getty Images hide caption

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President Barack Obama and Republican presidential candidate Mitt Romney at the first 2012 presidential debate in Denver, CO. SAUL LOEB/AFP/Getty Images hide caption

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A sign directs voters to polls at a polling station on Nov. 4, 2008, in Shallotte, N.C. Logan Mock-Bunting/Getty Images hide caption

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Mitt Romney takes the stage at a campaign rally at the Military Aviation Museum in Virginia Beach, Va., on Sept. 8. Brian Snyder/Reuters/Landov hide caption

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Shipping containers sit at a port in Tianjin, China, on Feb. 28. Alexander F. Yuan/AP hide caption

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In a 1988 debate against George H.W. Bush, Michael Dukakis's answer to a question about whether he would support the death penalty if his wife were raped and murdered is considered a huge stumble. LENNOX MCLENDON/ASSOCIATED PRESS hide caption

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