“NBC Nightly News” wrapped up the first quarter of 2015 as the No. 1-ranked evening newscast, even as the show endures a controversy involving its anchor. While Brian Williams serves out a six-month suspension over his discredited remarks about his war coverage in Iraq, his fill-in, Lester Holt, has continued to keep the news program on top in the ratings.

Media Life Magazine reports that “Nightly News” finished the quarter with an average audience of 9.51 million total viewers — ahead of ABC’s “World News Tonight with David Muir,” which averaged 9.10 million, and “CBS Evening News with Scott Pelley,” with 7.76 million.

In the key news demo of viewers 25-54, the NBC program led the way with 2.33 million viewers, followed by ABC with 2.26 million and CBS with 1.83 million.

However, ABC may be starting to chip away at NBC’s lead, especially in the key news demo.

Nielsen figures for the week ending March 29 show NBC with a narrow win in total viewers, while ABC squeezed ahead in average rating for the 25-54 demo. For the week, “NBC Nightly News” averaged 8.709 million total viewers, to 8.597 million for ABC’s “World News Tonight” and 6.739 million for “CBS Evening News.”

In viewers 25-54, ABC won the week ending March 29 with a 1.8 average rating, just ahead of NBC’s 1.7. CBS was third with a 1.2.