Newt Gingrich along with his wife, Callista, addresses supporters at the Hilton Hotel in Columbia, S.C. following his primary victory. South Carolina voters have chosen the GOP nominee since 1980.
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Republican presidential candidate former U.S. Sen. Rick Santorum speaks to supporters after announcing that he was endorsed Saturday by the evangelical Christian leaders group.
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Republican presidential candidates (from left) Ron Paul, Mitt Romney and Rick Santorum participate in the ABC News, Yahoo! News and WMUR Republican Presidential Debate at Saint Anselm College on Saturday in Manchester, N.H.
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Obama is surrounded by former presidents in the Oval Office in 2009. Two of his predecessors — George W. Bush and Bill Clinton — won two terms, while two others — George H.W. Bush and Jimmy Carter — left office after just one.