Not long ago, the names on the marquee would have been right at home on Fox News: Stephen K. Bannon, Tucker Carlson and Roger J. Stone Jr.
But Fox News ousted Mr. Carlson three months ago, and Mr. Bannon, Mr. Stone and a boisterous pro-Trump crowd at the Turning Point Action Conference were eager to take shots at the conservative network, arguing that it has not been sufficiently supportive of former President Donald J. Trump as he seeks to regain the office he lost in 2020.
At the two-day gathering, with thousands of pro-Trump activists in attendance this weekend in South Florida, jeers flew on Sunday at the mention of Rupert Murdoch, the Fox media mogul, as well as Speaker Kevin McCarthy.
And after Mr. Trump spoke to this crowd on Saturday, any of his Republican rivals for the party’s 2024 presidential nomination took the stage at their own peril.
In a speech on Sunday, Mr. Bannon, Mr. Trump’s onetime chief strategist who was found guilty of contempt of Congress, suggested that Mr. Murdoch had been using Fox News to hype Republican governors from battleground states to undermine Mr. Trump’s candidacy. He cited Gov. Ron DeSantis of Florida, Mr. Trump’s main rival in the party, who trails him by roughly 30 percentage points in national polls, as a cautionary tale.
“Come on down,” Mr. Bannon said. “Bring it because we’ll destroy you just like we destroyed DeSantis.”
Mr. Bannon — the host of a right-wing podcast, which he has used to promote election falsehoods and conspiracy theories — criticized Fox News for its lack of coverage of the pro-Trump conclave and called Mr. Trump’s political battles a “jihad.”
“Donald Trump is our instrument for retribution,” he said.
While Fox News did not carry the event on its main network, it did show conference speeches by Mr. Trump and the other Republican candidates on Fox Nation, its subscription streaming service. A Fox Corporation spokesman declined to comment on behalf of Mr. Murdoch.
Two of Mr. Trump’s long-shot Republican opponents — Asa Hutchinson, the former Arkansas governor; and Francis X. Suarez, the mayor of Miami — experienced the wrath of Mr. Trump’s supporters firsthand on Sunday when they were heckled and booed.
When Mr. Suarez, whom The Miami Herald has reported as being under F.B.I. investigation in a corruption case, stepped up to the microphone, a few people in the crowd yelled “traitor.”
He responded by mentioning his Cuban American heritage and saying that dissenting voices were welcome in America, unlike in his ancestors’ home country.
“It’s OK to have a little bit of hate,” Mr. Suarez said. Later, he asked conservative activists to chip in to his campaign.
Mr. Hutchinson paused his remarks as the crowd began chanting Mr. Trump’s name, and one of his biggest applause lines came when he mentioned his successor in the Arkansas governor’s office: Sarah Huckabee Sanders, Mr. Trump’s onetime White House press secretary.
Contending with cross-talk for much of his speech, Mr. Hutchinson said that Republicans needed to have respect for people with different opinions.
At the conference, attendees could attach sticky notes to cutouts of the Republican candidates’ heads.
A man placed one with a homophobic slur on the face of Mike Pence, Mr. Trump’s former vice president. Later, it appeared to have been removed. But a number of stickers branding Mr. Pence a “traitor” for refusing to overturn the 2020 election on Jan. 6, 2021, covered his face.
On a cutout of Nikki Haley, the former South Carolina governor and Mr. Trump’s United Nation’s ambassador, one sticky note said: “Woman in Politics? Cringe.”
At the event’s apex on Saturday, about 6,000 people filled the Palm Beach County Convention Center to hear Mr. Trump speak for nearly 100 minutes. Mr. Carlson ruminated about his dismissal from Fox News in April.
In a speech on Sunday, Mr. Stone, who had a felony conviction pardoned by Mr. Trump, claimed that federal prosecutors had offered him a deal to dredge up dirt implicating Mr. Trump in wrongdoing and recalled a predawn F.B.I. raid at his home in South Florida in 2019 during which he was arrested.
“I said, ‘You can go to hell,’” he said.