Thanks to its coverage of the second presidential debate between Barack Obama and John McCain, Fox News Channel became the most-watched network on cable last week, boasting an average primetime audience of 3.44 million viewers for the week, according to Nielsen Media Research. Some 8.77 million viewers watched the channel's debate coverage, with 7.05 million staying tuned for a special edition of Greta Van Sustern's On the Record , which followed. FNC also scored strongly among adults 25-54, coming in fourth among that demographic group. TBS was the second most-watched network during the week, thanks to its coverage of the baseball playoffs. It averaged 3.33 million total viewers for the week. However it ranked first in the key demographic groups, 18-34, 18-49, and 25-54.