That survey showed him leading his top rival, US Sen. Ted Cruz (R-Texas), 37% to 26%, among likely Iowa caucus-goers.

But the CNN poll was apparently too recent for Trump to tout at a Thursday rally in Las Vegas, Nevada. Instead, Trump boasted about his results in another recent Iowa poll, from Emerson College, that found him beating Cruz 33% to 23%.

"I'm winning like all of the polls — and by a lot," Trump declared.

"Emerson College, very important, great college. Trump 33%, Cruz 23%. Nice! Nice! Wow," he added.

After Trump heralded another survey, from North Carolina, the Republican front-runner said Cruz was tanking in the 2016 race.