Amy Brighton from Medina, Ohio, who opposes the new health care law, rallies in front of the Supreme Court on Tuesday. Charles Dharapak/AP hide caption

itoggle caption Charles Dharapak/AP

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

itoggle caption Marvin Gentry /Reuters /Landov

Former Massachusetts Gov. Mitt Romney addressed supporters at a Super Tuesday rally in Boston on Tuesday. His home state was one of the six he won Tuesday night. Jessica Rinaldi /Reuters /Landov hide caption

itoggle caption Jessica Rinaldi /Reuters /Landov

Former Massachusetts Gov. Mitt Romney waves to the crowd as he is introduced at the start of Wednesday night's Republican presidential debate in Mesa, Ariz. Ross D. Franklin/AP hide caption

itoggle caption Ross D. Franklin/AP

Republican presidential hopeful and former U.S. Sen. Rick Santorum speaks to supporters, flanked by his daughter, Elizabeth (left), and wife, Karen. Whitney Curtis/Getty Images hide caption

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Jan White, left, Brenda Robertson, center, and Janet Freixas, right, count paper ballots at the headquarters of the Douglas County Republican Party Saturday in Minden, Nev., following county-wide Nevada caucus meetings. Ted S. Warren/AP hide caption

itoggle caption Ted S. Warren/AP

Mitt Romney at his state campaign headquarters Tuesday in Tampa, Fla. Joe Raedle/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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