Former House Speaker Newt Gingrich, who wants to the the 2012 Republican presidential nominee, during a campaign event in Camp Hill, Pa., on Saturday (March 24, 2012). Jessica Kourkounis/Getty Images hide caption

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Former House Speaker Newt Gingrich. Win McNamee/Getty Images hide caption

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After his losses in Alabama and Mississippi on Tuesday, Newt Gingrich will face increasing pressure to drop out of the GOP race. Here he waves to supporters after speaking at a rally in Hoover, Ala., on Tuesday. Marvin Gentry /Reuters /Landov hide caption

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Republican candidate Newt Gingrich is counting on his promise of $2.50-per-gallon gas to return him to front-runner status. Evan Vucci/AP hide caption

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Former House Speaker Newt Gingrich waves during a campaign stop Friday in Peachtree City, Ga. Doing well in the state's primary is important for Gingrich because he represented a congressional district there for 20 years. Evan Vucci/AP hide caption

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Former House Speaker Newt Gingrich addresses the Conservative Political Action Conference in Washington, D.C., on Friday. Win McNamee/Getty Images hide caption

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On Thursday night in Jacksonville, Fla., Mitt Romney (right) went after Newt Gingrich from the start on topics such as immigration and colonizing the moon. Matt Rourke/AP hide caption

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