Mitt Romney, the Republican party's nominee in the 2012 presidential election, said Friday he will vote for Sen. Ted Cruz in next week's Utah nominating caucus.
"The only path that remains to nominate a Republican rather than Mr. Trump is to have an open convention. At this stage, the only way we can reach an open convention is for Senator Cruz to be successful in as many of the remaining nominating elections as possible," Romney wrote in a Facebook post.
The announcement comes as the Republican party continues to probe alternatives to Donald Trump as the businessman's lead in the party primary grows.
Romney depicted the state of Republican politics as a battle between "Trumpism" and Republican values.
"Trumpism has become associated with racism, misogyny, bigotry, xenophobia, vulgarity and, most recently, threats and violence. I am repulsed by each and every one of these," Romney wrote.
Romney, former governor of Massachusetts, continued to say that, while he likes the other candidate in the race, Gov. John Kasich, he believes that voting for Kasich would only contribute to Trump's victory.
Trump respond to Romney's Facebook comments on Twitter, referring to Romney as a failure in a string of tweets.
Earlier this month Romney delivered a scathing attack on Trump in a speech at the University of Utah, calling Trump "a phony" who is "playing the American public for suckers."
A number of Republican officials have shown their support for Cruz in recent days while falling short of endorsing the senator, who is currently in second place in the race for the GOP nomination. On Thursday, South Carolina Sen. Lindsey Graham said he would help Cruz's fundraising efforts but stopped short of offering his endorsement to his senate colleague.
Utah is among four states voting Tuesday. Nationally, Trump leads his rivals, having won 678 delegates so far, according to a count by The Associated Press. Cruz is in second place with 423 delegates, and Kasich is in third with 143.
One minute before Romney's post was set live, Trump took a shot at the Republican establishment, which Romney is associated with: "With millions of dollars of negative and phony ads against me by the establishment, my numbers continue to go up. Can anyone explain this?"
The Associated Press contributed to this report.