Kent Sorenson says he was paid for his endorsement of Ron Paul in the 2012 presidential campaign — and that the exchange was hidden from the public. Charles Dharapak/AP hide caption

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Republican vice presidential candidate, Rep. Paul Ryan waves with his family Wednesday at the GOP convention in Tampa. Also on stage: his daughter Liza, sons Charlie and Sam Ryan, wife Janna and mother Elizabeth. Win McNamee/Getty Images hide caption

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Ann Romney is hugged by her husband, Mitt, after she addressed delegates during the Republican National Convention in Tampa, Fla., on Tuesday. Rick Wilking/Reuters/Landov hide caption

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Ron Paul supporters pose with posters on the floor of the RNC on Monday in Tampa. They put "Ron Paul" over the word "We" on a GOP sign that says "We Can Do Better." Liz Halloran/NPR hide caption

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Rep. Ron Paul, R-Texas, brought thousands to the Sun Dome in Tampa on Sunday for a "we are the future" rally. Becky Lettenberger/NPR hide caption

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Rick Santorum told voters in Mandeville, La. on Wednesday that they were "not looking for someone who's the Etch A Sketch candidate." Sean Gardner /Reuters /Landov hide caption

itoggle caption Sean Gardner /Reuters /Landov

Jim Wilson of Buckingham, Va., who supports Republican presidential candidate Mitt Romney, walks past a bus during a Romney campaign stop Monday in Springfield, Ill. Steven Senne/AP hide caption

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You know you're campaigning in the South if you've got comedian Jeff Foxworthy by your side. Foxworthy introduces Mitt Romney at a campaign stop at the Whistle Stop Cafe, Monday, in Mobile, Ala. John David Mercer/AP hide caption

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