The second debate between President Obama and Mitt Romney reached nearly as many people as the first debate, according to Nielsen, reflecting robust and sustained interest in the presidential election three weeks before Election Day.
Nielsen said 65.6 million viewers watched the Tuesday night town hall format event on television at home, down just 2.4 percent from the debate on Oct. 3. Untold millions more watched the two debates on TV sets in public places and watched on computers, phones and tablets, but those viewers are not counted in Nielsen's totals.
Fox News, with 11.1 million viewers during the debate, enjoyed the biggest audience in its 16-year history on Tuesday. The cable channel has hit 11.1 million viewers just once before: during the vice presidential debate between Joseph R. Biden Jr. and Sarah Palin in 2008.
Two broadcast networks, NBC and ABC, drew more total viewers than Fox News, NBC with 13.8 million and ABC with 12.4 million. CBS had about 8.9 million viewers, CNN had 5.77 million and MSNBC had 4.87 million.
Though the total TV viewership was lower on Tuesday than it was two weeks ago for the first debate, some online sources said they saw an increase in traffic. NBCNews.com served up about 320,000 live video streams on Tuesday night, 30 percent more than it did during the first debate.
There tends to be one debate each presidential election cycle with a town hall format, where voters ask questions of the candidates. The town hall debate between Mr. Obama and John McCain in 2008, similarly held on a Tuesday night, drew 63.2 million viewers on TV at home, according to Nielsen. The town hall in 2004, held on a Friday night, drew 46.7 million.