Rep. Ron Paul. Patrick Smith/Getty Images hide caption

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Republican presidential candidate Newt Gingrich addressed large crowds at campaign stops like this one at Tommy's Ham House in Greenville, S.C. on Wednesday. Richard Shiro/AP hide caption

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Republican presidential candidate Newt Gingrich speaks to the crowd at the Naples Hilton on Friday in Naples, Fla. Scott McIntyre/AP hide caption

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Former House Speaker Newt Gingrich answers a question at Tuesday's Republican presidential debate in Washington, D.C. Mandel Ngan/AFP/Getty Images hide caption

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Newt Gingrich is shown teaching a class at West Georgia College (now known as the University of West Georgia) in the 1970s. As a politician, he has long stressed his background as a scholar. Courtesy of Gingrich Productions hide caption

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At a Republican presidential debate in Las Vegas last month, Newt Gingrich got zinged by rival Mitt Romney for coming up with idea of an individual insurance mandate. Ethan Miller/Getty Images hide caption

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In September 1994, then-House Minority Whip Newt Gingrich addressed Republican congressional candidates on Capitol Hill during a rally where they pledged a new "Contract with America." Months later, Republicans gained control of both houses of Congress for the first time in decades, and Gingrich became speaker of the House. John Duricka/AP hide caption

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Former Speaker of the House Newt Gingrich has relished attacking the journalists questioning him during the GOP debates. Scott Olson/Getty Images hide caption

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Republican presidential candidate Newt Gingrich greets a supporter at a kickoff party for the opening of a campaign office in Manchester, N.H., on Nov. 11. Winslow Townson/AP hide caption

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Former House Speaker Newt Gingrich, shown in May speaking at the Georgia Republican Party Victory Dinner in Macon, Ga., says he was acting as a "historian" when Freddie Mac paid him consultant fees of $300,000. Jessica McGowan/Getty Images hide caption

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Newt Gingrich. Ethan Miller/Getty Images hide caption

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