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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President Obama and other members of his national security team monitored the mission that ended with the death of Osama bin Laden in May 2011. Pete Souza/White House hide caption

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What a difference 14 years makes. Here, Bill Clinton departs the White House on July 31, 1998, after telling reporters he wouldn't take questions about the Monica Lewinsky investigation. Tim Sloan/AFP/Getty Images hide caption

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President Obama delivers remarks at a campaign event on July 5 in Parma, Ohio. Chip Somodevilla/Getty Images hide caption

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President Obama meets with Jason and Ali McLaughlin and their son, Cooper, while visiting their home in Cedar Rapids, Iowa. Susan Walsh/AP hide caption

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President Obama at a stop on his bus tour of Ohio in Port Clinton on July 5. Jim Watson/AFP/Getty Images hide caption

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President Obama waves after signing the Affordable Care Act at the White House on March 23, 2010. Chip Somodevilla/Getty Images hide caption

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