Businessman Donald Trump leads the Republican presidential field by a double-digit margin, while former neurosurgeon Ben Carson has faded into third place, according to a new national poll.

The Quinnipiac University survey finds that Mr. Trump draws 27% of Republican vote nationwide, while Sen. Marco Rubio is in second place at 17%. Mr. Carson is tied for third place nationally with Sen. Ted Cruz, with each man drawing 16% of the vote.

Former Florida Gov. Jeb Bush draws 5%, while the rest of the crowded GOP field remains under 3%.