BREAKING: Marco surges to lead!

Sen. Marco Rubio has emerged as the strongest candidate in the GOP presidential field, topping the rest of his announced and potential rivals for the nomination and running best against top Democratic candidate Hillary Rodham Clinton, according to a new Quinnipiac University Poll Thursday.

Mrs. Clinton still leads Mr. Rubio in a national head-to-head match-up, 45 percent to 43 percent, but the 2-point margin is down from the 5-point lead she held over him a month ago in the same survey.

Mr. Rubio announced his candidacy earlier this month and has shot to the top of the GOP field nationally, garnering 15 percent of support among likely GOP primary voters — up from just 5 percent support a month ago. He has surmounted Wisconsin Gov. Scott Walker, who was first in the March poll but who slipped to third place in this survey. Former Florida Gov. Jeb Bush, meanwhile, remains in second place, with 13 percent of GOP support.

“The youngest member of the GOP presidential posse moves to the front of the pack to challenge Hillary Clinton whose position in her own party appears rock solid,” said Tim Malloy, assistant director of the poll.