Diane Sawyer’s hourlong primetime interview with Hillary Clinton drew a decent crowd of a little over 6 million viewers for ABC on Monday, but it ranked last among the major networks in its timeslot in key demos. Monday’s top honors in young adults on the broadcast nets went to NBC’s “American Ninja Warrior” and Fox’s “24: Live Another Day,” while CW’s “Whose Line Is It Anyway” looked strong kicking off the night.

According to preliminary national estimates from Nielsen, “Hillary Clinton: Public and Private with Diane Sawyer,” an interview with the former U.S. Secretary of State in advance of her new book “Hard Choices,” averaged a 1.0 rating/3 share in adults 18-49 and 6.1 million total viewers in the 9 o’clock hour, according to Nielsen. It ran fourth among the networks for its timeslot in both 18-49 and adults 25-54 (1.8/5).

In total viewers, the Clinton interview finished a close second for its timeslot, behind Fox’s “24.”

ABC adjusted its lineup to make room for the Clinton interview, airing a special recap of “The Bachelorette” season at 8 (0.9/3 in 18-49, 4.0 million viewers overall) instead of its usual two-hour original episode. And the lower lead-in from “Hillary Clinton” dragged down 10 p.m. drama “Mistresses” (0.9/3 in 18-49, 3.6 million viewers overall), which fell 25% (0.3) from its week-ago season premiere.

Fox won the night in young adults with its firstrun combo of “MasterChef” (1.5/5 in 18-49, 4.0 million viewers overall) and “24: Live Another Day” (1.6/5 in 18-49, 6.3 million viewers overall), even though they were down three-tenths and two-tenths, respectively, from last week.

At NBC, a repeat of “Last Comic Standing” (1.1/4 in 18-49, 4.0 million viewers overall) was followed by “American Ninja Warrior” (1.7/5 in 18-49, 4.9 million viewers overall), which was down 11% (0.2) week to week but was the broadcast leader in 18-49 with all four of its half-hours from 9 to 11.

CBS aired repeats of “2 Broke Girls” (1.0/3 in 18-49, 4.7 million viewers overall), “Mom” (1.0/3 in 18-49, 4.6 million viewers overall) and “Mike & Molly” and both 9 (1.2/4 in 18-49, 5.2 million viewers overall) and 9:30 (1.2/4 in 18-49, 5.3 million viewers overall). A special original of “48 Hours” closed out the night (0.9/3 in 18-49, 5.7 million viewers overall), tying ABC’s “Mistresses” in 18-49 and pulling ahead in 25-54 (1.9 to 1.5) as well as total viewers.

CW’s “Whose Line Is It Anyway” (0.7/2 in 18-49, 1.9 million viewers overall) was up 40% (0.2) week to week in the demo, and followed that up with a good number for its 8:30 p.m. repeat (0.6/2 in 18-49, 1.6 million viewers overall). It was followed by an original episode of low-rated drama “Beauty and the Beast” (0.3/1 in 18-49, 0.9 million viewers overall).

Preliminary 18-49 averages for the night: Fox, 1.6/5; NBC, 1.5/5; ABC and CBS, 1.0/3; CW, 0.5/1.

In total viewers: Fox, 5.5 million; CBS, 5.2 million; NBC, 4.6 million; ABC, 4.5 million; CW, 1.3 million.