ABC 'Nightly News' reaches milestone among younger viewers

ABC's "World News Tonight" is sealing its rise to the top of the evening news competition with a milestone victory.

ABC has consistently beaten NBC's "Nightly News" for several months now among all viewers.

But last week ABC won for only the second time in 136 weeks among 25-to-54-year-old viewers that advertisers are most anxious to reach. Start winning that demographic consistently, and dollars will flow.

David Muir's newscast has reached several milestones recently among all viewers, winning last season for the first time since Peter Jennings was the anchor 21 years ago.

Its margin of victory in February was its largest in that month in 22 years, the Nielsen company said Tuesday.