Donald Trump, ratings kingmaker, bestowed big numbers on Fox News and CNN last Friday after both channels rolled out coverage of the Republican front-runner’s rally in Mobile, Alabama.

Trump, standing out more than usual on screen with a bright red hat saying “Make America Great Again,” pulled in 810,000 viewers for Fox News in “the demo,” viewers from the 24-54 age group prized by advertisers, Nielsen reported. The rally took place 8-10 p.m., during Bill O’Reilly and Megyn Kelly, with 3.6 million viewers total.

A week earlier, "The O'Reilly Factor" at 8 p.m. drew 301,000 in the demo and "The Kelly File" at 9 p.m. drew 273,000, TVByTheNumbers reported.

Meanwhile, CNN picked up 322,000 in the demo at 9 p.m. and and 1.3 million total viewers an hour earlier.

Still, Trump’s magic has its limits: Last Wednesday, Fox beat CNN in the 9 p.m. hour even as the latter ran an hourlong special with Trump and anchor Chris Cuomo. Fox took 513,000 in the demo and 2.6 million in total while CNN got 369,000 and 1.1 million, respectively -- and that was with a guest host on “The Kelly File.”

Nielsen said the Trump special put CNN up 48 percent in total viewers and up 21 percent in the demo compared to the same time last year.  

The last time CNN was that high in total viewers was in April, during its coverage of the Baltimore riots.