Ask yourself this question about any Presidential candidate.

If they aren't re-elected after a first term, will they actually leave office?

For all the Presidents in my lifetime, I have no doubt that they all would have left office voluntarily if they weren't re-elected. Many of them did. 

Nixon even left office voluntarily when it became clear that Congress would convict him and remove him from office, before his term was up.

Had Clinton been convicted in his impeachment trial, I don't doubt he would have left.

Had George W. Bush not been re-elected, even though he was a perfectly awful president, I don't doubt he would have retired.

Trump? No, I don't think he would leave voluntarily. 

No point asking him this, or any other question, btw, because he never answers truthfully. Which btw, is something the press should take into account. Why bother asking him any questions. Seriously, why do you bother. You're giving him an air of legitimacy that he doesn't deserve. The man can't answer anything truthfully.