Donald Trump would fire himself from his own presidential campaign if his poll numbers started to drop significantly, the "Apprentice" star told CNBC's John Harwood on Thursday.

"Right now I'm leading every poll -- and in most cases big. And I'm leading Iowa, I'm leading New Hampshire, I'm leading South Carolina, I'm leading everything," Trump said.

"That's good. (But) if that changed - if I was like some of these people at 1 percent and 2 percent, there's no reason to continue forward."

If he were to lose a key primary, meanwhile, Trump said he would consider to "step away" depending on the circumstances, he noted, according to the Hill.

"Well, I'm not a masochist, OK?" the real-estate tycoon said.

So far, however, Trump has little to worry about, the New York Post reported: The 69-year-old continues to lead the RealClearPolitics average of recent national polls with 23 percent, well ahead of retired neurosurgeon Ben Carson (16 percent), former Hewlett-Packard chief executive Carly Fiorina (12 percent), Florida Sen. Marco Rubio (10 percent) and former Florida Gov. Jeb Bush (9 percent).

Trump promised that he was "in this for the long haul" but said he did not suggest that he would mind returning to his business ventures if his campaign is were to falter, CBS Washington reported.

"That doesn't mean someday I don't wake up and I say, 'Wow, I'm really tanking.' Well, if I tank, sure, I go back to the business. Why wouldn't I?" he said.

When Harwood pressed Trump on one of the issues that has haunted his campaign -- the nagging question about how he would implement many of his promises -- the business mogul quipped about his supposed superhero qualities, CNN reported.

"We don't have Superman presidents," Harwood said as he challenged his guest to detail a plan on how to deport the estimated 11 million undocumented immigrants in the United States, an effort Trump has said he would carry out in a "humane" manner.

"No," Trump replied with regard to the "Superman" comment, "but we will if you have Trump."