Republican presidential candidates Sen. Marco Rubio and businessman Donald Trump during a commercial break at a Republican presidential primary debate at Fox Theatre in Detroit on March 3, 2016. (AP Photo/Carlos Osorio)
Republican front-runner Donald Trump (L) speaks with Reince Priebus, chairman of the Republican National Committee, at a debate sponsored by Fox News in Detroit on March 3. (Chip Somodevilla/Getty Images)
Republican presidential candidates (L-R) Sen. Marco Rubio, Sen. Ted Cruz, Donald Trump and Ohio Gov. John Kasich greet each other following a debate sponsored by Fox News at the Fox theatre in Detroit on March 3. (Chip Somodevilla/Getty Images)
Republican front-runner Donald Trumps takes a sip of water during a commercial break at the Republican debate moderated by FOX News in Detroit on March 3. (AP Photo/Paul Sancya)
Republican presidential hopeful Ohio Gov. John Kasich (R) laughs with Sen. Ted Cruz during a Republican presidential primary debate sponsored by FOX News in Detroit on March 3. (AP Photo/Paul Sancya)
Republican presidential candidates Donald Trump and Sen. Ted Cruz greet each other following a debate sponsored by Fox News in Detroit on March 3, 2016. (Chip Somodevilla/Getty Images)
Republican presidential candidate Sen. Ted Cruz talks to moderator Megyn Kelly after a Republican presidential primary debate at Fox Theatre in Detroit on March 3, 2016. (AP Photo/Paul Sancya)
Republican presidential candidates Sen. Marco Rubio and Sen. Ted Cruz shake hands during a debate sponsored by Fox News in Detroit on March 3, 2016. (Chip Somodevilla/Getty Images)
Moderators Chris Wallace and Megyn Kelly take the stage before a Republican presidential primary debate at Fox Theatre in Detroit on March 3. (AP Photo/Paul Sancya)
Former Texas Governor Rick Perry (C) stands behind Republican presidential candidate Sen. Ted Cruz as he speaks to the media in the spin room after a Republican debate hosted by Fox News in Detroit on March 3, 2016. (Joe Raedle/Getty Images)
Heidi Cruz, wife of Republican presidential candidate Sen. Ted Cruz, waits before a Republican presidential primary debate at Fox Theatre in Detroit on March 3, 2016. (AP Photo/Paul Sancya)
Republican presidential candidate businessman Donald Trump arrives at the spin room with his wife Melania after a Republican presidential primary debate at Fox Theatre in Detroit on March 3, 2016. (AP Photo/Carlos Osorio)
Moderators (L-R) Chris Wallace, Megyn Kelly and Bret Baier appear during a Republican presidential primary debate at Fox Theatre in Detroit on March 3, 2016. (AP Photo/Paul Sancya)
Republican presidential candidates Sen. Marco Rubio and Donald Trump participate in a debate sponsored by Fox News at the Fox Theatre in Detroit on March 3, 2016. (Chip Somodevilla/Getty Images)
Moderators (L-R) Bret Baier, Megyn Kelly and Chris Wallace take the stage before a Republican presidential primary debate at Fox Theatre in Detroit on March 3. (AP Photo/Paul Sancya)
