Republican presidential candidate Mitt Romney arrives onstage early Wednesday morning in Boston, moments before conceding defeat in the 2012 presidential election. Emmanuel Dunand/AFP/Getty Images hide caption

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Mitt Romney talks to reporters on his campaign plane on Election Day. "I'm very proud of the campaign we've run," he said. "No campaign is perfect." Emmanuel Dunand/AFP/Getty Images hide caption

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Casino magnate Sheldon Adelson at the presidential debate between Mitt Romney and President Obama, in Denver on Oct. 3. Adelson invested millions in an effort to help elect Romney — but only after bankrolling a superPAC for former House Speaker Newt Gingrich in his anti-Romney Republican primary battle. Nicholas Kamm/AFP/Getty Images hide caption

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Mormons line up outside the historic Salt Lake Temple for an annual conference in April 2010. George Frey/Getty Images hide caption

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Tagg Romney, the eldest son of presidential candidate Mitt Romney, shakes hands with Barbara Irby at GOP headquarters in Lynchburg, Va., last month. Sam O'Keefe/AP, News & Daily Advance hide caption

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Republican presidential candidate Mitt Romney makes his case about Medicare during a briefing in South Carolina in August. Evan Vucci/AP hide caption

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Mitt Romney helps collect and pack donated goods for those affected by Hurricane Sandy, in Kettering, Ohio, on Tuesday. Emmanuel Dunand/AFP/Getty Images hide caption

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Republican presidential candidate Mitt Romney speaks about the Supreme Court ruling on health care in Washington on June 28. Charles Dharapak/AP hide caption

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Mitt Romney speaks Monday at a campaign event at Avon Lake High School in Avon Lake, Ohio. Tony Dejak/AP hide caption

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Mitt Romney greets supporters Sunday during a campaign rally in Findlay, Ohio. Justin Sullivan/Getty Images hide caption

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