On Tuesday night, 63.2 million U.S. viewers watched the second presidential debate between Senators John McCain and Barack Obama.
The TV audience for the senators’ second meeting easily surpassed that of their first debate, which drew an audience of 52.4 million on Friday, Sept. 26.
During the previous presidential campaign, 46.7 million viewers tuned in for President Bush and John Kerry’s second debate on Oct. 8, 2004. 
See more historical debate ratings.

According to data from across 11 networks, the first presidential debate on September 26 between John McCain and Barack Obama drew 52.4 million viewers.
The TV audience for the first presidential debate of the 2008 election was roughly 16% smaller than the audience for the first debate between President Bush and John Kerry during the 2004 election, which drew 62.5 million viewers on September 30, 2004. See more historical debate ratings.
ABC, CBS, FOX, NBC, Telefutura, Telemundo, BBC-America, CNBC, CNN, FOX  News Channel, and MSNBC aired live coverage of the McCain/Obama debate …

During the first presidential debate on September 26, Barack Obama’s comments on oil independence, health care, the Iraq War, and Al Qaeda drew the most positive responses from a panel of uncommitted, registered voters who allowed CBS and Nielsen to capture their real-time reactions to the first presidential debate Friday night.
As they watched the debate, panel members turned a dial between 0 and 100 to indicate their reactions to the candidates’ discussion. 100 indicates a “very positive” response, 0 corresponds with a “very negative” response, and 50 is neutral. Nielsen …

The combined overall household rating for Friday night’s presidential debate, in 55 of the 56 local television markets where Nielsen maintains electronic TV meters, was 34.7.
One rating point equals 1% of the total TV audience in a given market.
Coverage of the first presidential debate between Barack Obama and John McCain aired on ABC, CBS, NBC, FOX, PBS, CNN, Telemundo, TeleFutura, BBCA, Fox News, MSNBC, and C-Span.
Previously, Nielsen reported that the combined overall household rating for the top 55 local markets was 33.2. That rating excluded households that …