A U.S. soldier watches members of the Afghan Public Protection Force arrive at a ceremony on the outskirts of Kabul on Thursday. Ahmad Jamshid/AP hide caption

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Mitt Romney waits to speak while being introduced Monday during a campaign stop in Mobile, Ala. Win McNamee/Getty Images hide caption

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This Nov. 4, 2008, file photo shows Republican Rep. Jean Schmidt being congratulated by supporters in Loveland, Ohio. Schmidt is up against three other Republicans in the March 6 primary. David Kohl/AP hide caption

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Former Massachusetts Gov. Mitt Romney shakes hands at a campaign rally at Capital University in Bexley, Ohio, on Wednesday. Justin Sullivan/Getty Images hide caption

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Prospective voters listen to Republican presidential candidate Newt Gingrich, accompanied by his wife, Callista, on Feb. 7 at Cincinnati's Price Hill Chili restaurant. Evan Vucci/AP hide caption

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