Mitt Romney and other Republican establishment figures pressed ahead Sunday with their campaign to block Donald Trump from capturing the party's presidential nomination, casting him as a shady businessman who rips people off with questionable enterprises such as the defunct Trump University.
"I want to make sure that the American people are not subject to the same kind of scam as we nominate a president," Romney told NBC's "Meet the Press."
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But since the Republican donor class fell into a panic after Trump dominated last week's Super Tuesday contests, the pugnacious front-runner has, fittingly, taken an in-your-face approach to its assault on his candidacy, including millions of dollars in advertising against him.
Trump has persisted in making racially tinged remarks and joking about the size of his male anatomy. He has openly criticized big-business donors that shape the Republican Party's policy agenda. And he has warned the GOP establishment that its attacks risk turning off his huge following.
Romney is "not looking at me, he's looking at all of us," Trump told a crowd in New Orleans on Friday night. "We have had one of the greatest things politically to happen in many, many decades," he said. "Millions of people are going out to vote that never gave a damn before."
Hurling insults at rivals Ted Cruz and Marco Rubio, Trump took credit for the record-shattering turnout in the 19 states that have voted so far. "It's not because of lying Ted or little Marco," he said of the Texas and Florida senators. "It's because of Trump, I hate to say it."
Trump has won 12 states, Cruz six, and Rubio one. (After Rubio lost all four contests held Saturday, Trump called on him to drop out of the race.) Nearly 3.6 million Americans have voted for Trump, giving him a wide delegate lead.
But with Romney, the GOP presidential nominee in 2012, and others ratcheting up efforts to stop Trump, the split between Republicans leaders and the billionaire's millions of largely blue-collar voters poses an existential threat to the party.
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"I think we are seeing a great political party shatter before our eyes," Peggy Noonan, a speechwriter for President Reagan, wrote in a Wall Street Journal column Saturday.
At the New Orleans rally Friday night, Trump was unabashed in defying Republican orthodoxy, saying "the hell with these conservative guys" who criticize his call for a 35% tax on goods sold by U.S. companies that move to Mexico.
"The hell with no taxes, folks," Trump hollered to the raucous crowd in a packed airplane hangar.
After weathering sharp criticism from Republican congressional leaders and rivals for his hesitancy last week in disavowing support from David Duke and the Ku Klux Klan, Trump has not shied from new racially charged appeals.
In New Orleans, he said the election of Hillary Clinton would mean "another four years of Barack Hussein Obama," using the middle name that right-wing critics have cited to imply the Christian president is really a Muslim.
Trump, who recently asked on Twitter whether Obama might have attended the funeral of Supreme Court Justice Antonin Scalia if it had taken place in a mosque, was once the most prominent celebrity to question whether he was born in Kenya and thus unqualified to serve as president.
At a rally Saturday in Orlando, Trump told supporters, "We have a terrible president who happens to be African American," giving no explanation of why race was relevant to his critique of Obama's policies.
Earlier, in Wichita, Kan., Trump again defended the size of his penis, responding to Rubio's taunt that Trump had small hands "and you know what they say about men with small hands."
"Look at these hands!" Trump told the crowd. "These hands hit a golf ball 285 yards. Look at these hands." (Romney said Trump's remarks about his anatomy in Thursday's debate were "something I don't want my grandkids to watch.")
In West Palm Beach, Fla., on Saturday night, Trump criticized businesses that are bedrock GOP donors. He singled out the oil, gas, electric utility, pharmaceutical and lumber industries, saying they were seeking a more malleable Republican nominee.
At the same time, Trump has tried to calibrate his criticism of the party he hopes to lead. In response to a question after victories in Louisiana and Kentucky on Saturday, Trump said he would help the party raise money if he wins the nomination. Such fundraising could undercut his appeal as an outsider who refuses to take special-interest donations.
With mixed success, Trump has also tried to walk back comments that struck some as extreme. He continues to use his support for torturing terrorists as an applause line, but has agreed he would not order the military to break the laws that ban it. Instead, he now says he will seek to change the law so torture is allowed.
"You have to play the game the way they're playing the game," Trump said on CBS' "Face the Nation."
As for attacks on his business record, Trump has used Twitter to mock allegations in lawsuits that Trump University defrauded students who wasted tens of thousands of dollars on its real estate seminars for little in return: "The primary plaintiff in the phony Trump University suit wants to abandon the case. Disgraceful!"
And in Wichita, Trump boasted that he won a government contract to convert a landmark Washington post office into a hotel in part because his finances were "incredible" and "they want to make sure it gets built; they don't want to have it stuck."
Left unaddressed was Rubio's accusation that he stiffed buyers who put down deposits on condos at a proposed Trump resort in Baja California but lost their money when the 2008 market crash struck, leaving the project unbuilt.