I call it truthful hyperbole. It's an innocent form of exaggeration - and a very effective form of promotion.
"I will be changing very rapidly. I'm very capable of changing to anything I want to change to."
Trump’s support dropped 9 points after the SC debate:
....”The [ CNN/ORC] poll did show that Mr. Trump’s level of support was slightly different based on whether the interviews, conducted from Feb. 10-15, were done before or after the boisterous GOP debate on Saturday, Feb. 13. Forty percent backed Mr. Trump in interviews conducted before the debate, compared to 31 percent who supported him afterward.”
http://www.washingtontimes.com/news/2016/feb/17/donald-trump-leads-ted-cruz-16-points-sc-poll/