“His promises are as worthless as a degree from Trump University. He's playing the American public for suckers: He gets a free ride to the White House and all we get is a lousy hat.”
Romney ripped into Trump's foreign policy and his temperament, and called Trump's praise of Russian President Vladimir Putin and criticism of former president George W. Bush, for instance, a case of "evil trumping good.”
"Dishonesty is Trump's hallmark," Romney said, adding later, "We will only really know if he is the real deal or a phony if he releases his tax returns and the tape of his interview with The New York Times."
A businessman himself, Romney went after Trump's economic policies and failed business ventures.
"But wait, you say, isn't he a huge business success that knows what he's talking about? No, he isn't. His bankruptcies have crushed small businesses and the men and women who worked for them. He inherited his business, he didn't create it," Romney said to applause from the audience, going on to say: "A business genius he is not."
"Think of Donald Trump's personal qualities, the bullying, the greed, the showing off, the misogyny, the absurd third-grade theatrics," Romney posed to the audience.
Romney also argued that the New York real estate developer will lose to former Secretary of State Hillary Clinton if she is the Democratic nominee.
"Mr. Trump is directing our anger for less than noble purposes," Romney said, acknowledging American voters' anger. "He creates scapegoats of Muslims and Mexican immigrants, he calls for the use of torture. He calls for killing the innocent children and family members of terrorists. He cheers assaults on protesters. He applauds the prospect of twisting the Constitution to limit first amendment freedom of the press. This is the very brand of anger that has led other nations into the abyss."