“The Rachel Maddow Show” surpassed “Tucker Carlson Tonight” in March among 25- to 54-year-old viewers, the demographic that determines advertising rates.

Maddow was on track to win again in April. But on Monday night the cable news ratings race changed dramatically. Carlson moved from 9 p.m. to 8, replacing Bill O’Reilly, and Fox’s 5 p.m. talk show “The Five” moved to 9.

Maddow may or may not benefit from the change. Regardless, executives all across television news have already taken notice of her recent wins.

According to Nielsen data, Maddow also narrowly topped Fox’s 8 p.m. hour last week, when Dana Perino and Greg Gutfeld filled in for O’Reilly.