While that audience is slightly down from the 67.2 million who saw the first debate, it is still a huge TV gathering -- up by 2.4 million viewers from the second debate in 2008 when Obama drew rock-star ratings every time he appeared on TV.
The third and final debate will be held Monday with Bob Scieffer, of CBS News, as moderator.
Here's the release from Nielsen:
An estimated 65.6 million people tuned in to watch the second debate between incumbent President Barack Obama and Republican candidate Mitt Romney on Tuesday, October 16.
The town hall-style debate, hosted by Hofstra University in New York and moderated by CNN’s Candy Crowley, was carried across 12 networks.
The second presidential debate, and third overall, in this political season’s debate quartet netted 2.4 million more viewers than the second presidential debate between then Sen. Barack Obama and Sen. John McCain in 2008.