Campaign signs for Republican presidential candidate, former Pennsylvania Sen. Rick Santorum, cover the frozen ground as the campaign bus carrying Republican presidential candidate, former ... more 
Campaign signs for Republican presidential candidate, former Pennsylvania Sen. Rick Santorum, cover the frozen ground as the campaign bus carrying Republican presidential candidate, former Massachusetts Gov. Mitt Romney, passes by en route to a campaign stop at the San Marino Club, Saturday, Feb. 25, 2012, in Troy, Mich. (AP Photo/Eric Gay) less 
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Associated Press | Photo By Eric Gay
Sun, Feb 26, 2012 7:55 AM EST