With sports disrupting the other networks, ABC became the only clear winner in Sunday’s first televised presidential debate, which was seen in nearly 40% of U.S. households in the overnight metered markets.

If those levels hold up nationally, it will mean about 40 million homes viewed the debate, which drew an aggregate 38.3 rating and 58 share on ABC, NBC and Fox Broadcasting Co.

PBS reported a 3.4/6 in the U.S.’ five largest markets (the only cities for which numbers were available) and cable webs CNN and C-SPAN didn’t have figures at presstime. Regardless, with them added in, more than six out of 10 viewers were watching the debates, although there was no appreciable tune-in compared to normal viewership levels for that time period.

CBS ended up being shut out of the debate coverage because of an extra-inning Major League Baseball playoff game but didn’t significantly affect viewership, posting only an 8.5/13 in the Nielsen overnights from 7-8:30 p.m. (ET), coinciding with the debate.

Similarly, NBC joined the debate in progress in much of the country due to regional football coverage that ran until about 4:20 p.m. (PT), leaving ABC and Fox Broadcasting Co. as the only over-the-air outlets to air the debate live in its entirety.

That left ABC as the clear choice among broadcast outlets, averaging a 19.2/ 29 for the 90-minute debate and maintaining that level with its half-hour post-debate analysis, which drew a 19.1/28. NBC posted a 13.8/22 during the first half-hour (largely accounted for by the football overrun) and then a 14.6/ 22 for the balance of the debate and its analysis.

Fox, carrying its first presidential debate, posted a 4.6/7, then saw its numbers more than double immediately following the debate (eschewing analysis) with entertainment programming. CBS also saw its average jump at 8:30 at the start of the Atlanta-Pittsburgh game.

A CBS News spokesman acknowledged that the situation was “somewhat frustrating,” with Dan Rather and other CBS News staffers waiting to pick up the coverage as the game dragged on. The network added that it was locked into its baseball contract and had “tried to deal with this (scheduling problem) about a year ago” in discussions with the political parties.

Debate coverage was sustaining (meaning it ran without advertising) and as a result won’t be included in network rating averages, although the analysis that followed will be.

ABC’s movie “Overexposed” also topped the first half of NBC miniseries “Lady Boss” in the overnights and, with the preemption of “60 Minutes” and “Murder, She Wrote,” should have cemented a weeklong win for the alphabet network.

Locally, KABC-TV’s advantage was even more pronounced, with a 16.2/28, compared to a 6.6/11 for KNBC-TV and 3.3/6 for Fox’s KTTV.

Tonight’s vice presidential debate and next Monday’s final presidential encounter will both precede sports programming and are fixed at 4 p.m. (PT). This Thursday’s face-off is tentatively set for 6 p.m. but would be switched to accommodate a possible Game Seven in the American League Championship Series.

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