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Republican presidential front-runner Donald Trump pushed back Wednesday night against what appears to be a growing movement among the party establishment — including a few of his former rivals — to at least slow down his march to the convention with enough delegates in hand to claim the nomination.

Speaking with Sean Hannity on a special Fox News town hall, Trump accused GOP lawmakers opposed to his campaign of "taking advantage of our country."

The billionaire businessman called his campaign a movement "of competence and common sense and low taxes and [secure] borders and it would be so foolish to give it away."

Trump was referring to a conference held by the conservative American Enterprise Institute at Sea Island off the coast of Georgia over the weekend, where one of the topics reportedly was stopping Trump from securing the Republican nomination.

The conference reportedly was attended by Senate Majority Mitch McConnell, House Speaker Paul Ryan and other key Republican congressmen.

"I know all these people," Trump told Hannity. "These are people that are taking advantage of our country. They don’t want to have strong borders. They want stuff flowing across the borders. They don’t want to have taxation when countries treat us unfairly because they benefit from that."

"Politicians will do what’s right for the people that gave them the money," Trump added later, "not what's right for the country."

Former GOP presidential candidate Jeb Bush also planned to meet with Trump's rivals on Thursday ahead of a GOP debate in Florida, fueling speculation that he's preparing to endorse a candidate challenging Trump.

Florida Sen. Marco Rubio, meanwhile, told Fox News that he would not drop out of the Republican presidential race before next week's Florida primary, saying, "we're gonna fight this thing through Tuesday ... and we're going to go on."

Rubio denied multiple reports that he had discussed the possibility of dropping out before the winner-take-all contest.

Speaking with Fox News’ Megyn Kelly, Rubio said: "I have never discussed dropping out with anyone on my team, or anyone on the planet Earth ... I'm the only one who can beat Donald Trump in Florida.”

A Fox News poll released Wednesday showed Rubio trailing Trump by 23 percentage points among likely Republican voters in Florida.

"I honestly don’t believe Donald Trump will be the nominee," Rubio said. "I continue to believe it's going to be me, and it's got to start here in Florida."

Rubio also dismissed the possibility that he would form a so-called "unity" Republican ticket with Texas Sen. Ted Cruz, Trump's closest challenger in the delegate race, calling it " the kind of drama that makes it interesting in TV to speculate about."

"At some point we're all going to team up," Rubio said in reference to the non-Trump candidates. "We're all going to be on the same team, I hope.”

Cruz told Kelly that Rubio and Kasich were "good, honorable people, but neither of them has a path to the nomination."

"Head-to-head, not only do I beat Donald Trump," Cruz said, "but I defeat him resoundingly."

Cruz also walked back his earlier opposition to a possible convention fight between himself and Trump if neither man reaches the required 1,237 delegates during the primaries.

"Look, [Ronald] Reagan and [President Gerald] Ford battled it out at a contested convention [in 1976]," Cruz said. "That's what conventions are for." However, Cruz restated his opposition to a so-called brokered convention, calling it "a fever dream of the D.C. establishment" and warning of "an open revolt" among Republican voters if it came to pass.

Cruz later turned his rhetorical fire against Trump and Rubio over immigration reform and the so-called "Gang of Eight" bill in 2013.

"When Marco Rubio stood with Barack Obama and [Sen.] Chuck Schumer and [then-Senate Majority Leader] Harry Reid ... I stood with millions of Americans," Cruz told Kelly. "Not only was Donald Trump nowhere to be found, he was funding the Gang of Eight. He gave $50,000 to five of its members."

Cruz also accused Rubio of lowering the tone of the campaign, saying, "I have no views whatsoever on any part of Donald Trump’s anatomy," an apparent reference to Rubio jabbing Trump's "small hands" at a Virginia campaign stop.

For his part, Rubio told Megyn Kelly that he regretted the remark, saying "my kids were embarrassed by it, my wife didn’t like it, I don’t think it reflects [well]; that’s not who I am."

Ohio Gov. John Kasich, who has staked his campaign's future on victory in next Tuesday's Ohio primary, told Fox News' Greta Van Susteren that he would "probably not" pick up enough delegates in other contests to overtake Trump, but noted that voters had only "picked about half the delegates [so far] this year ... anything is possible."

A Fox News poll released Wednesday showed Kasich leading Trump by five percentage points among likely Republican voters in the Buckeye State.

"We're going to win Ohio," Kasich told Van Susteren. "That's not even a question for me. It's about what we do after that and all the places we have to go. But we're not taking it for granted."

Trump has 458 delegates to Cruz's 359 following Tuesday's contests, in which Trump won the Mississippi and Michigan primaries as well as the Hawaii caucus. Cruz also picked up a win in the Idaho primary. Rubio is a distant third with 151 delegates, while Kasich has 54.