According to last night’s preliminary ratings, the second presidential debate between John McCain and Barack Obama scored significantly better ratings than the first match-up between the two candidates, though still far short of the monster audience that tuned in for last week’s vice presidential debate. Yesterday’s contest averaged 33 million viewers in the country’s 55 largest TV markets, nearly 30 percent more than the 25.6 million who tuned in for the Sept. 26 McCain-Obama showdown. (The increase is likely due in part to the simple fact that the first debate aired on a Friday, when viewership levels are notoriously low.) Of course, neither debate came close to last Thursday’s vice presidential showdown between Sarah Palin and Joe Biden, which nabbed almost 70 million viewers to make it one of the most-watched debates in history. ABC again fared the best with last night’s debate viewership, grabbing an average 14.5 million, while only 9.7 million watched on NBC and 9.3 million on CBS. (Fox data released by Nielson only covered the first hour of the 90-plus-minute debate, during which the network averaged 5.2 million viewers.) The breakdown for the first presidential debate was 10.2 million for ABC, 7.8 million for NBC, and 7.6 million for CBS.

As for non-election-related programming, CBS’ NCIS (15.7 million) won the night over the ABC’s Dancing With the Stars results show (which earned 13.4 million viewers airing at 8 p.m. in the East and 9 p.m. in the West), NBC’s The Biggest Loser: Families (6.3 million), and Fox’s House rerun (6.3 million). Over at The CW, 90210 pulled in 3.1 million viewers (down only 3 percent from last week’s 3.2), and Privileged continued to improve, even against the debates in the 9 p.m. slot, by attracting 2.3 million (up 20 percent from last week’s 1.9).

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