The third and final debate between President Obama and Republican nominee Mitt Romney attracted 59.2 million viewers, according to ratings firm Nielsen.
Audience levels for the matchup, which centered on foreign policy issues, were down 12% compared with the first debate this month between the presidential contenders. The Oct. 3 debate, when Obama appeared off his game, was the most watched, attracting 67.2 million viewers. The second debate drew 65.6 million.
Monday's debate faced stiff competition from "Monday Night Football" on ESPN and Fox's broadcast of a clinching Major League Baseball division series game, in which the San Francisco Giants throttled the St. Louis Cardinals to win a ticket to the World Series.
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Ten networks provided live coverage of the debate.
Viewership was up about 5% compared with the final debate four years ago, when then-Sen. Obama sparred with Sen. John McCain (R-Ariz). That 2008 matchup was watched by 56.5 million people.
NBC generated the largest audience Monday night with 12.4 million viewers. The debate was staged at Lynn University in Boca Raton, Fla., and moderated by CBS News' Bob Schieffer. ABC News garnered 11.7 million viewers, according to Nielsen.
Nipping at ABC's heels was Fox News Channel, which drew its largest audience in the network's 16-year history with an average of 11.5 million viewers. That topped the 11.1 million viewers who tuned in to Fox News last week for the second debate moderated by CNN's Candy Crowley.
For the second time, Fox News' coverage boasted more viewers than CBS, which pulled in 8.4 million viewers Monday.
CNN's coverage attracted an audience of 5.8 million while MSNBC played before 4.1 million.
In contrast, "Monday Night Football" on ESPN averaged 10.7 million people and the baseball game on Fox averaged 8.1 million.
Viewership levels dropped for each debate.
The demographic that quickly lost interest were 18-to-34-year-olds, according to Nielsen. More than 12 million viewers in that group watched the first debate Oct. 3. On Monday, 9.6 million young adults tuned in.
As expected, people over 55 showed up in the greatest numbers. On Monday, 28.5 million viewers in that demographic watched the debate, down from nearly 31 million in the same age group who saw the first debate. Nielsen said 17.1 million viewers age 35 to 54 watched Monday's debate, down from 19.9 million for the first debate.
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