Supporters listen to Republican presidential candidate Rick Santorum at The Ravine in Bellevue, Wis., on March 24. Some voters in the state are complaining about a barrage of negative ads in advance of Tuesday's primary.
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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).
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