A volunteer arranges buttons before Mitt Romney speaks Wednesday in Clinton, Iowa. Chris Carlson/Associated Press hide caption

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Minnesota Rep. Michele Bachmann signs autographs at the Pizza Ranch in Indianola, Iowa, on Wednesday. The restaurant was largely empty aside from a few local Iowans, media and Bachmann staff. Becky Lettenberger//NPR hide caption

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A young supporter backs former Massachusetts Gov. Mitt Romney as he speaks on Wednesday at Homer's Deli and Bakery in Clinton, Iowa. Chris Carlson/Associated Press hide caption

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Texas Gov. Rick Perry attends the Westside Conservative Club breakfast Wednesday in Urbandale, Iowa. Eric Gay/Associated Press hide caption

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An Occupy camp at College Green Park in Iowa City, Iowa. The camp was mostly empty aside from three men. Becky Lettenberger/NPR hide caption

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Herman Cain shakes hands with a family at a Petersburg, Fla. book signing, Wednesday, Oct. 5, 2011.

Chris O'Meara/AP hide caption

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Florida Sen. Marco Rubio speaks at the Ronald Reagan Presidential Library in Simi Valley, Calif. in August. Rubio's dispute with Univision has provoked a boycott of the network's presidential debate.

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