Republican presidential candidates, from left, Ohio Gov. John Kasich, New Jersey Gov. Chris Christie, Sen. Marco Rubio, R-Fla., businessman Donald Trump, Sen. Ted Cruz, R-Texas, retired neurosurgeon Ben Carson and former Florida Gov. Jeb Bush participate during the Fox Business Network Republican presidential debate at the North Charleston Coliseum, Thursday, Jan. 14, 2016, in North Charleston, S.C. (AP Photo/Chuck Burton) ** FILE **