GOP rivals coordinating to stop Donald Trump?

Ted Cruz: Brokered convention would be “eno... 10:04

Florida Sen. Marco Rubio's campaign gave its supporters in Ohio the green light to vote for Ohio Gov. John Kasich in the state's primary next week, acknowledging that Kasich stands the best chance of defeating Donald Trump in the state.

"I suspect that a voter in Ohio that doesn't want Donald Trump to win Ohio may very well conclude that the best way to stop him in Ohio is to vote for John Kasich," Rubio told reporters in Florida on Friday. "And I respect that."

Marco Rubio: Trump’s policies would “not ... 05:09

He later added, "If a voter in Ohio is motivated by stopping Donald Trump and comes to the conclusion that John Kasich is the only one that can beat them there, then I expect that's the decision they'll make."

Kasich's campaign declined to return the favor, though, suggesting voters should select whomever they'd like and arguing that Kasich is the best man for the job in every state.

Texas Sen. Ted Cruz, another GOP competitor, laughed when asked about Rubio's suggestion in an interview with Sean Hannity on Friday, calling it the Washington establishment's "last gasp."

But as Trump races toward the GOP nomination, Cruz, like his competitors, is trying mightily to halt the frontrunner's momentum by courting other candidates' supporters.

Asked last week by "Face the Nation" host John Dickerson whether he'd been approached by another campaign about an alliance to stop Trump, Cruz would only say, "I'm having the conversations with all sorts of people."

Ted Cruz: A president should not "embarrass" ... 00:59

"What we're seeing is, we're seeing supporters from other candidates coming and joining us, whether they were with Jeb Bush, whether they were with Chris Christie, whether they were with Ben Carson, whether they have been with Marco Rubio or Rand Paul," he said. "We're seeing people come together because they are recognizing that their candidates were not in a position beat Donald. And if Donald is the nominee, it is a catastrophe. Hillary wins."

Pressed on whether he'd act jointly with another candidate to defeat Trump, Cruz replied, "My focus is very simple: It is on winning 1,237 delegates to be the Republican nominee."

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