Republican presidential candidate and Texas congressman Ron Paul at Iowa State University in Ames on Aug. 13, 2011. Scott Olson/Getty Images hide caption

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Ron Paul on 'Talk of the Nation'

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Left to right: Former Sen. Rick Santorum; Rep. Michele Bachmann; former House Speaker Newt Gingrich; former Massachusetts Gov. Mitt Romney; Rep. Ron Paul; former Minnesota Gov. Tim Pawlenty; entrepreneur Herman Cain. Emmanuel Dunand /AFP/Getty Images hide caption

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NPR's Ari Shapiro on 'Morning Edition'

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Sarah Palin

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