Major news stories -- including the fatal shooting of an unarmed African-American teenager in Missouri by a white police officer, and escalating tensions in the Middle East -- helped boost ratings for cable news channels during August.
Fox News was unshakable as the No. 1 cable news channel last month, averaging 1.8 million viewers in prime time. Fox News' prime-time ratings jumped 15% compared with August 2013.
CNN's audience grew nearly 40% in prime time to 629,000 viewers a night, according to Nielsen rankings released by the networks Wednesday. CNN is owned by Time Warner.
August also marked the second straight month that CNN's audience levels eclipsed those generated by MSNBC during the entire day.
MSNBC also made gains -- but not on pace with CNN or Fox News.
The Comcast Corp.-owned channel saw its prime-time audience increase 10% to 571,000 viewers a night.
CNN's stalwarts posted gains. "The Situation Room with Wolf Blitzer," was the second-most popular cable news program in its time period (behind Fox News' "The Five"). Blitzer's audience grew 55% to 690,000 viewers a night compared with August 2013.
"The Five" on Fox News averaged 2 million viewers a night.
"The Lead with Jake Tapper" on CNN grew its viewership 64% last month to an average of 642,000 viewers.
"The O'Reilly Factor," with Bill O'Reilly was the top cable news program, attracting an average of 2.7 million viewers.
Two other Fox News shows rounded out the top three. "The Kelly File" with Megyn Kelly was the second-most popular program with nearly 2.3 million viewers. "Hannity" attracted an average of 1.6 million viewers.