'Nightline,' 'UpClose' follow in third

HOLLYWOOD — Despite an improved performance by the CBS primetime schedule, the net’s “Late Show with David Letterman” has fallen further behind NBC’s “Tonight Show with Jay Leno” in the early going this season.

According to Nielsen estimates for the week of Sept. 23-27, Leno’s NBC program averaged 5.9 million viewers (down 7% from last year) while Letterman’s CBS show drew 4.1 million (down 31%). That gap of 1.8 million is considerably larger than the 1.3 million during the same week last year, when the New York-based “Late Show” saw a bit of a ratings surge with guests including Rudy Giuliani.

Similar pattern holds up in the key demo of adults 18-49, where Leno’s 2.3 rating tops Letterman’s 1.7 by 35% — up from 14% a year ago. ABC’s team of “Nightline” (3.9 million, 1.3/5 in A18-49) and “UpClose” (2.4m, 0.8/4) lagged in third.

CBS is hoping that stronger ratings in the 10 p.m. hour on weeknights will help Letterman close the gap. Last week, CBS moved up to No. 2 in the hour, gaining by double-digit percentages while No. 1 NBC was declining.

Primetime perf has boosted the ratings of the Eye net’s local affils’ 11 p.m. newscasts, but so far, not Letterman’s show that follows.

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