Mitt Romney, the GOP standard-bearer in 2012, delivered one of the loudest warnings to date against the man who may carry the party's torch in 2016, Donald Trump — using words like "phony" and "fraud" in a speech Thursday intended to rally anti-Trump forces in the party.
The 25-minute speech at the University of Utah included the type of forceful rhetoric that cannot be unsaid in the event that Trump wins the nomination and Republicans try to coalesce around him.
It was a startling rebuke by a party leader against a presidential front-runner, just two days after scores of voters across the country chose Trump as their candidate.
The critique laced into Trump's character, his policy positions, his business acumen and his temperament, warning that the country's future was at risk in Trump's hands.
It laid traps for Trump as well, baiting the candidate to attack Romney personally to demonstrate he is a bully, daring him to open his tax returns and challenging him to release off-the-record comments he made to the New York Times editorial board about his signature immigration issue.
"Let me put it plainly, if we Republicans choose Donald Trump as our nominee, the prospects for a safe and prosperous future are greatly diminished," Romney said. "His domestic policies would lead to recession. His foreign policies would make America and the world less safe. He has neither the temperament nor the judgment to be president. And his personal qualities would mean that America would cease to be a shining city on a hill."
It is unknown what Romney's speech will accomplish in political terms. Trump's core supporters have stuck with him and often celebrated establishment attacks against their favored candidate.
Romney's own struggle to win the party's 2012 nomination and his ultimate defeat also raises questions about how much influence he still wields among the rank and file.
"Mitt Romney is a stiff," Trump said on NBC's "Today" show Thursday morning.
But Romney appears to be trying to mobilize a group of Republicans not currently committed to Trump who increasingly say in polls that they might be satisfied with Trump as the nominee.
For months, party leaders alarmed by Trump's rise have argued that the best way to defeat him is consolidating the GOP field and uniting behind a single alternative.
But Romney suggested a new path — urging Republicans to vote for whatever candidate has the best chance to beat Trump in their home state.
"That means that I would vote for Marco Rubio in Florida, for John Kasich in Ohio and for Ted Cruz or whichever one of the other two contenders has the best chance of beating Mr. Trump in a given state," Romney said.
That strategy would prevent Trump from gaining a majority of party delegates on the first ballot at the nominating convention this summer. If no one wins on the first ballot, convention delegates would be released to pick any candidate, allowing them to build new coalitions — or even to choose a compromise candidate like Romney.
It's a high-risk strategy, given the likelihood that it would alienate many Trump supporters, who already distrust the Republican establishment.
Romney tried to insulate himself from any suggestions that his attack against Trump would prop up the likely Democratic nominee, Hillary Clinton, instead casting Trump in that role.
"A person so untrustworthy and dishonest as Hillary Clinton must not become president. But a Trump nomination enables her victory," Romney said.
South Carolina Sen. Lindsey Graham and others also have begun to argue that the party must distance itself from Trump, even if it costs them the general election.
"I think the party can survive Donald Trump as long as we don't lose our heart and soul," Graham said in an interview with several reporters Wednesday in the Capitol. "We can't survive if we embrace those things about Mr. Trump that put him outside of the American mainstream. We can survive with him being the nominee and losing."
The clash between Trump and Romney, two very wealthy men, is emblematic of the GOP's internal struggle. Romney once courted Trump and praised him effusively when he won his endorsement in 2012. But since Trump has rallied the angriest elements of his party, he has consciously tried to tear down many of the things Romney has stood for, casting Romney as a horrible candidate who got decimated in his own run for the White House.
"Failed candidate Mitt Romney, who ran one of the worst races in presidential history, is working with the establishment to bury a big 'R' win!" Trump wrote in one of several tweets and Facebook messages aimed at Romney on Wednesday and Thursday.
Romney anticipated more attacks in his speech.
"Watch, by the way, how he responds to my speech today," Romney said. "Will he talk about our policy differences, or will he attack me with every imaginable low road insult? This may tell you what you need to know about his temperament, his stability and his suitability to be president."
Romney warned that Trump's threats to impose tariffs would kill American jobs, that his refusal to overhaul safety-net programs would lead to deficits and that his foreign policy positions — including his complimentary words for Russian leader Vladimir Putin — would endanger the country and its leadership position in the world.
In particular, he faulted Trump for "the most ridiculous and dangerous idea of the entire campaign season: 'Let ISIS take out Assad,' he said, and then we can pick up the remnants."
In what may have been the sharpest insult, he mocked Trump's business know-how.
"His bankruptcies have crushed small businesses and the men and women who worked for them," Romney said, in a critique that echoed Democrats' attacks against Romney during the 2012 campaign. "He inherited his business; he didn't create it. And whatever happened to Trump Airlines? How about Trump University? And then there's Trump Magazine and Trump Vodka and Trump Steaks, and Trump Mortgage? A business genius he is not."