Republican presidential candidate Mitt Romney pauses during a visit to St. Paul's Lutheran Church while campaigning in Berlin, N.H., on Dec. 22. Charles Krupa/AP hide caption

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Then-Sen. John F. Kennedy participates in a question-and-answer session with the Ministers' Association of Greater Houston on Sept. 12, 1960, in Houston. In a speech to the group, Kennedy addressed concerns about his Catholicism and his run for the presidency. Houston Chronicle/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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Mitt Romney narrowly won in Michigan Tuesday night. For Super Tuesday, he'll set his sights on Ohio, Massachusetts, Vermont and Virginia. Bill Pugliano/Getty Images hide caption

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