SIMI VALLEY, CA - SEPTEMBER. 16: Republican presidential candidates, (L-R) George Pataki, Rick Santorum, Louisiana Gov. Bobby Jindal and U.S. Senator Lindsey Graham (R-SC) stand onstage during the presidential debates at the Reagan Library on September 16, 2015 in Simi Valley, California. Fifteen Republican presidential candidates are participating in the second set of Republican presidential debates. (Photo by Justin Sullivan/Getty Images)
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SIMI VALLEY, CA - SEPTEMBER. 16: Republican presidential candidates, (L-R) George Pataki, Rick Santorum, Louisiana Gov. Bobby Jindal and U.S. Senator Lindsey Graham (R-SC) stand onstage during the presidential debates at the Reagan Library on September 16, 2015 in Simi Valley, California. Fifteen Republican presidential candidates are participating in the second set of Republican presidential debates. (Photo by Justin Sullivan/Getty Images)
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Republican presidential candidates, from left, former Pennsylvania Sen. Rick Santorum, former New York Gov. George Pataki, Sen. Rand Paul, R-Ky., former Arkansas Gov. Mike Huckabee, Sen. Marco Rubio, R-Fla., Sen. Ted Cruz, R-Texas, retired neurosurgeon Ben Carson, businessman Donald Trump, former Florida Gov. Jeb Bush, Wisconsin Gov. Scott Walker, businesswoman Carly Fiorina, Ohio Gov. John Kasich, and New Jersey Gov. Chris Christie take the stage during the CNN Republican presidential debate at the Ronald Reagan Presidential Library and Museum on Wednesday, Sept. 16, 2015, in Simi Valley, Calif. (AP Photo/Chris Carlson)
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