Republican presidential front-runner Donald Trump is leading Florida Sen. Marco Rubio in the latter's home state by 23 percent among Florida's likely Republican voters just days before the March 15 primary, prompting the former chairman of the state's Republican Party to declare that Rubio's campaign is "pretty much finished."

The latest figures from Florida came from two sources—Fox News and the Quinnipiac University polls—which both released their survey results on Wednesday. The Quinnipiac University poll shows Trump with 45 percent support to Rubio's 22 percent. The Fox News poll shows Trump ahead 43 percent to Rubio's 20 percent.

Sen. Ted Cruz of Texas took 18 percent and while Ohio Gov. John Kasich had 8 percent in the Quinnipiac University poll.

Rubio is making a last stand in Florida, but many of his closest supporters have told The Washington Post that it's highly unlikely for the GOP's once rising star to win in his home state.

"It's certainly a possibility that he could lose on Tuesday, and perhaps by double digits," John McKager "Mac" Stipanovich, a Rubio supporter, told the Post.

On Wednesday night, Rubio and his wife were greeted by a near empty football stadium in Hialeah when they held a rally there, Newsmax reported.

Al Cardenas, the former head of the state's GOP and long-time chairman of the American Conservative Union, said Rubio's personal attacks on Trump backfired on the Florida senator.

"Those exchanges with Mr. Trump were damaging," he said, adding that he sees little hope for a Rubio comeback.

Ohio Gov. John Kasich is faring better in his home state, which will also hold a winner-take-all primary on March 15.

Kasich is leading Trump, 34 percent-29 percent, according to one of the polls. However, the Quinnipiac University poll shows Kasich trailing Trump 38 - 32 percent, compared to a 31 - 26 percent Trump lead on Feb. 23. Cruz has 16 percent, with 9 percent for Rubio.

Trump predicted on Wednesday that if he wins both Florida and Ohio, he will be unstoppable on his path to the Republican nomination.

"I think if I win those two, I think it's over," Trump told CNN's Anderson Cooper.

Cruz has emerged as Trump's biggest rival for the nomination, but he is running in third in both Florida and Ohio, according to the new polls.

Trump said his huge primary victories on Tuesday, particularly in Michigan, has left the "Never Trump" movement—a loose collection of advocacy groups, donors and elected officials—"mortally wounded."

Trump pointed out that Rubio, once envisioned as his chief rival, has been seriously damaged. He said Rubio can only blame himself for what happened after his rival resorted to racy attacks. Trump maintained that Rubio's personal attacks did not affect him psychologically.

"Nobody gets under my skin," he said. "But he was really rude. And, in fact, for a while, I wasn't even sure if what I was seeing was right."