A night of big shifts in cable's typical lineup brought a win Monday for Fox News Channel, which topped primetime among both adults 25-54 and total viewers. Most importantly, Tucker Carlson shifted into ousted Bill O'Reilly's 8 o'clock hour as the night's dominant telecast.

The first official night without The O'Reilly Factor saw the 8 p.m. telecast of Tucker Carlson Tonight average 3.2 million viewers and 636,000 adults 25-54, per early returns from Nielsen Media. Though it will be some time before there's a sense of how Carlson's numbers compare to O'Reilly's, he at least successfully kept the hour as cable news' biggest during his premiere telecast. O'Reilly's final Monday on the air, his penultimate Fox News telecast on April 10, averaged 3.7 million viewers and 635,000 adults 25-54 — so while Carlson may not have pulled the same audience, he was dead even in the demo.

Also good news for Fox News, which officially severed ties with O'Reilly last week amidst mounting claims of sexual harassment, is that The Five made a solid segue into the 9 o'clock hour — Carlson's old time slot. The panel show edged past MSNBC's The Rachel Maddow Show for a win with 2.8 million viewers and 568,000 adults 25-54. (Maddow averaged 2.2 million viewers and 523,000 adults 25-54.)

Fox News wasn't the only network making tweaks on Monday. CNN kicked off its trial run of Jake Tapper at 9 p.m. The anchor averaged a robust No. 3 in the hour with 881,000 viewers and, more importantly, 304,000 adults 25-54.

There were no changes at 10 o'clock, which saw Fox News' Sean Hannity tops in both total viewers and adults 25-54.

Full primetime averages are below.

Monday, April 24 (8-11 p.m.)

1. FNC: 2.8 million viewers; 582,547 adults 25-54

2. MSNBC: 1.8 million viewers; 424,425 adults 25-54

3. CNN: 944,570 viewers; 328,705 adults 25-54

Rupert Murdoch sent a memo to staff, congratulating them on the network's ratings and "stellar performance."

Read Murdoch's memo below.

Dear Colleagues:

Last night’s ratings are in and I couldn’t be more proud to announce that, not only did FOX News beat all other cable news competition with our new primetime debut, but we also increased our ratings 31% in total viewers and 54% in the demo compared to last year. This was a stellar performance that couldn’t have happened without the amazing effort and dedication from everyone on the team over the last week.

I know the last few weeks have been tough for everyone here, but our passion for news and commitment to our viewers continue to lead us through.

Congratulations and thank you for all your hard work!

Best,

Rupert Murdoch