The Dublin-based prediction market site Intrade lets users bet money on whom they expect to win a variety of U.S. political races, including the presidential race. NPR/Intrade screen grab hide caption

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Republican presidential candidate Mitt Romney shakes hands during a rainy campaign rally Monday in Newport News, Va. Evan Vucci/AP hide caption

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President Obama speaks during a campaign event at George Mason University in Fairfax, Va., on Friday. Pablo Martinez Monsivais/AP hide caption

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Federal Reserve Chairman Ben S. Bernanke in a hearing of the Joint Economic Committee on Capitol Hill in June. Brendan Smialowski/AFP/Getty Images hide caption

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Paul Ryan waves as he takes the stage at the Republican National Convention in Tampa, Fla., on Aug. 29. Ryan has been celebrated as a deficit hawk with bold vision, but some critics have called his record on deficit-reduction "dismal." Chip Somodevilla/Getty Images hide caption

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House Budget Committee Chairman Paul Ryan, R-Wis., shakes hands with Federal Reserve Chairman Ben Bernanke at the close of the committee's hearing on the state of the economy in February 2011. J. Scott Applewhite/AP hide caption

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