True to form, Donald Trump minced no words as he mocked conservative media personality Glenn Beck today, calling him “a stone cold loser.”

“He’s a sad sack, and he cries,” Trump told a crowd at Dordt College, a Christian school in the heart of rural evangelical northwest Iowa.

Beck was planning to campaign in Iowa on Saturday for Texas Sen. Ted Cruz, now the real estate developer’s No. 1 rival for the Republican presidential nomination.

Trump also boasted of how loyal his supporters appear to be. “I could stand in the middle of Fifth Avenue and shoot somebody, and I wouldn’t lose any voters,” he said.

He focused frequently on Beck, though, telling the audience more than once that Beck “got fired from Fox.” Beck also recently apologized for saying that Trump had voted for President Barack Obama, which the New York billionaire has denied.

There were other targets of Trump insults at the candidate’s campus rally in Sioux Center. Among them were Amazon founder Jeff Bezos (his ownership of the Washington Post is “a tax scam,” Trump said), Secretary of State John F. Kerry (“not street-wise”) and GOP presidential hopeful Jeb Bush (not just “low energy,” but also “a sad case”).

At great length, Trump trashed editors and writers at the National Review, which dedicated its latest issue to attacking him. “Mostly losers,” he said.

Reprising one of his main attacks against Cruz, Trump tried to stoke doubts about whether the senator’s birth in Canada, albeit to an American mother, might disqualify him for the presidency. “He could run for the prime minister of Canada, and I wouldn’t even complain, because he was born in Canada,” Trump said.

The Cruz campaign has tried to raise doubts among Iowa conservatives about Trump’s ideological moorings, publicizing his past support for abortion rights and the favorable remarks he has made about Obama, Bill and Hillary Clinton and other Democrats.

In Sioux Center, Trump ridiculed suggestions that he used to be more liberal. “So what,” he said. “So was Ronald Reagan.”

As for Beck, he had his own stinging rebuke for Trump:

In a tweet, this message was relayed. @glennbeck just told Iowa voters that if @realdonaldtrump wins in Iowa then “it’s going to be a snowball to hell.”