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CNN  — 

Alarm bells must be going off inside Fox News.

The firing of the right-wing network’s most popular host, the extremist Tucker Carlson, not only depressed the channel’s own prime time ratings Monday, but breathed life into its smaller competitor, Newsmax.

When Brian Kilmeade filled in on Monday evening for Carlson, who spent years as the unquestionable ratings king at Fox News, the channel drew an average of 2.6 million viewers and 294,000 in the key advertiser-coveted 25-54 demo, according to Nielsen Media Research. That’s very good by normal cable standards. It’s even good by Fox News standards. But, in context of the numbers his predecessor regularly posted, it was a notable dip.

Compare Kilmeade’s Monday ratings to the previous start of the weeks in which Carlson helmed the hour. When Carlson hosted on April 17, he averaged 3.2 million total viewers and 445,000 in the key demo. On April 10, Carlson averaged 3.1 million total viewers and 438,000 in the key demo. And on April 3, Carlson averaged 3.2 million total viewers and 435,000 in the key demo.

Now, to be fair, no one expected Kilmeade to be able to match Carlson in the ratings — especially after only one night. Carlson’s ratings dominance was why he had that 8pm perch. Even longtime host Sean Hannity found himself placing second to Carlson. If it were easy to command an audience the size of Carlson’s, then there would be no reason for Rupert and Lachlan Murdoch to have paid the now-fired host a reported $20 million annual salary.

What is most significant, however, about Monday’s ratings data is its revealing of a dramatic audience swell at Newsmax, unlike anything the channel has seen in recent memory outside of its broadcasts of a Donald Trump rally. The smaller right-wing television network, with a prime time helmed by the election denier Greg Kelly and ex-Fox News host Eric Bolling, saw its numbers explode in the hours following Carlson’s ouster.

Last Monday, for instance, Newsmax averaged just 146,000 total viewers at 8pm. Last night, the audience was more than triple that, with an average of 531,000 total viewers.

The numbers suggest that some of Carlson’s audience migrated over to Newsmax to sample the competitor’s showing. Whether they stay at the channel and continue grazing is an open question. But on Monday, a not-so-insignificant chunk of Carlson’s fanbase appeared to wander outside the Murdoch-verse for their 8pm infotainment.

This precise viewer exodus is what alarmed the Murdochs and Fox News personnel in the wake of the 2020 election, putting them on “war footing” and ultimately giving way to the events that culminated in the company’s historic $787.5 million settlement with Dominion Voting Systems last week. At that point in time, Fox News had angered its audience by having accurately called the election for then-candidate Joe Biden. This time, the channel has alienated its audience by firing its most-prized host.

For now, the anger doesn’t appear to be quite as palpable. And it must be underscored again that this is only a single night’s worth of data. But if it manages to become a trend, it will certainly be cause for distress over on Avenue of the Americas.