Sean Hannity

NEW YORK — Sean Hannity says a media watchdog is guilty of “liberal fascism” for targeting advertisers on his Fox News Channel show, as one company announced Wednesday that it would no longer hawk its wares there.

The Chicago-based Cars.com said that it had been “watching closely” and recently decided to suspend its backing of Hannity.

Hannity, the sole survivor from Fox’s once stable and powerful prime-time lineup, has been a strong backer of President Donald Trump and believes the president is under attack from media and opponents who want to destroy him.

On Wednesday, Hannity said he would no longer talk about a discredited story involving a murdered Democratic National Committee chairman after speaking to the man’s family, and after Fox had earlier retracted an online story it had written about the case.

Uncertainty over whether Hannity would defy his network’s bosses over the story led to big ratings on Wednesday. The show reached 2.5 million viewers, or 50 percent more than it had for the same night a year earlier, the Nielsen company said.

On Wednesday, Hannity sent a steady stream of tweets that targeted Media Matters for America, the liberal lobbyists who a day earlier had posted a list of his show’s advertisers on its website. Targeting a show’s advertisers is a potent line of attack in television; the swift abandonment of Bill O’Reilly’s advertisers last month after the revelation of settlements paid to women to quiet harassment charges was widely considered a factor in his firing by Fox.

Media Matters is “targeting my advertisers to silence my voice,” Hannity tweeted. “They hope to get me fired. Rush (Limbaugh), O’Reilly, (Glenn) Beck, (Don) Imus and now me.” He posted a series of links to articles about Media Matters’ funding, and ties to figures reviled by many conservatives, like George Soros and Bill Clinton.

Media Matters denied that it was mounting a pressure campaign focusing on Hannity’s advertisers. The organization’s president Angelo Carusone said he hadn’t spoken to any sponsors. He said he wanted advertisers to be aware of Hannity’s “volatility” as part of a general Media Matters campaign to get them to think about advertising on Fox.