FILE - In this Jan. 16, 2012, file photo Republican presidential candidates former Massachusetts Gov. Mitt Romney, center, former Pennsylvania Sen. Rick Santorum, left, and former House Speaker Newt ... more 
FILE - In this Jan. 16, 2012, file photo Republican presidential candidates former Massachusetts Gov. Mitt Romney, center, former Pennsylvania Sen. Rick Santorum, left, and former House Speaker Newt Gingrich in Myrtle Beach, S.C. Millions of dollars spent by Romney allies on TV ads attacking his two main rivals have helped him pull ahead in the race. Campaign veterans say that Santorum and Gingrich feel the commercials were pointedly unfair, and that's a big reason they keep fighting despite Romney's delegate count. (AP Photo/Charles Dharapak, Pool) less 
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Associated Press | Photo By Charles Dharapak, Pool
Sun, Mar 18, 2012 10:19 AM EDT