Thanks to the current nomination calendar, U.S. presidential candidates (like Chris Christie, pictured at the 2015 Iowa State Fair) get lots of practice at flipping pork chops. Scott Olson/Getty Images News hide caption

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Former Pennsylvania Sen. Rick Santorum campaigning in Des Moines, Iowa. Andrew Harnik/AP hide caption

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Santorum Struggles To Regain 2012 Momentum
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Republican presidential candidates, from left, Bobby Jindal, Rick Santorum, George Pataki, and Lindsey Graham take the stage during the CNBC Republican presidential debate at the University of Colorado on Wednesday. Mark J. Terrill/AP hide caption

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Preparations underway in the Media Center at the third Republican debate on the campus of the University of Colorado in Boulder, Colo. Robyn Beck/AFP/Getty Images hide caption

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Republican presidential candidates (left-right) Bobby Jindal, Rick Perry, Rick Santorum, Carly Fiorina and George Pataki on stage during the first "kid's table" debate last month. John Minchillo/AP hide caption

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Why Should Candidates Show Up To The 'Kids' Table' Debate?
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Republican presidential candidates from left, Jim Gilmore, Lindsey Graham, Bobby Jindal, Rick Perry, Rick Santorum, Carly Fiorina, and George Pataki take the stage for a pre-debate forum at the Quicken Loans Arena, Thursday, Aug. 6, 2015, in Cleveland. Seven of the candidates have not qualified for the primetime debate. Andrew Harnik/AP hide caption

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Former Florida Gov. Jeb Bush poses with supporters for photos during a fundraiser in May. Alan Diaz/AP hide caption

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Billionaire Or Bust: Who Are Rich Backers Lining Up With?
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Sen. Ted Cruz, R-Texas, apologized Wednesday after making a joke about Joe Biden while the vice president was mourning the death of his son. Charles Dharapak/Associated Press hide caption

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