Jeb Bush, former Governor of Florida and 2016 Republican presidential candidate, right, waves as he and John Kasich, governor of Ohio and 2016 Republican presidential candidate, arrive on stage during a presidential candidate debate in Milwaukee, Wisconsin, U.S., on Tuesday, Nov. 10, 2015. The fourth Republican debate, hosted by Fox Business Network and the Wall Street Journal, focuses on the economy with eight presidential candidates included in the main event and four in the undercard version. Photographer: Daniel Acker/Bloomberg via Getty Images

Jeb Bush, former Governor of Florida and 2016 Republican presidential candidate, right, waves as he and John Kasich, governor of Ohio and 2016 Republican presidential candidate, arrive on stage during a presidential candidate debate in Milwaukee, Wisconsin, U.S., on Tuesday, Nov. 10, 2015. The fourth Republican debate, hosted by Fox Business Network and the Wall Street Journal, focuses on the economy with eight presidential candidates included in the main event and four in the undercard version. Photographer: Daniel Acker/Bloomberg via Getty Images