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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)
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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