Story highlights Conservative group calls for unity ticket against Trump

Group leaves door open to supporting third party

(CNN) Prominent conservatives led by Erick Erickson on Thursday called for a unity ticket and a convention fight to stop Republican front-runner Donald Trump, a sign of the growing desperation in the party establishment to find an alternative to the billionaire businessman.

"If that unity ticket is unable to get 1,237 delegates prior to the convention, we recognize that it took Abraham Lincoln three ballots at the Republican convention in 1860 to become the party's nominee and if it is good enough for Lincoln, that process should be good enough for all the candidates without threats of riots," Erickson wrote in a statement after conservatives gathered in Washington to discuss ways to thwart Trump's march to the nomination.

The long and contentious meeting at the Army Navy Club included discussion about a unity ticket involving Texas Sen. Ted Cruz and Ohio Gov. John Kasich, according to a source familiar with the conversation. But the group decided not to commit to that pairing "because of the egos involved," according to the source.

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Around the time the meeting broke up, Florida Sen. Marco Rubio made his first public statements on Capitol Hill after dropping his presidential bid on Tuesday.

"Hopefully there's time to still prevent a Trump nomination, which I think would fracture the party and be damaging to the conservative movement," Rubio said.

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