CNN has struggled in the prime-time ratings as cable news viewers have increasingly sought edgier, more opinionated programming. Brown, a former NBC News reporter, advertised a "no bias, no bull" persona in a straight news and analysis program with a concentration on politics.
Brown said it was her decision to leave. She said she could say she was leaving to spend more time with her two young children or pursue new opportunities, and both would be partly true.
"But I have never had much tolerance for others' spin, so I can't imagine trying to stomach my own," she said. "The simple fact is that not enough people want to watch my program, and I owe it to myself and to CNN to get out of the way so that CNN can try something else."
Her time slot is dominated by Fox News Channel's Bill O'Reilly, who is averaging 3.3 million viewers this year, and MSNBC's Keith Olbermann, who has 1 million viewers. The longtime rivals are political polar opposites who host the top-rated hours on their respective networks.
CNN's prime-time problems with Brown, Larry King and Anderson Cooper have given rise to dozens of armchair program directors who have published advice this spring. Now CNN's executives will have their first shot at doing something new.
CNN/U.S. President Jon Klein said he respects Brown's decision and wishes her well. "We will announce our programming plans in the coming weeks," he said.
Brown's decision comes at a time when CNN has reportedly been talking with CBS News about ways to combine forces, although nothing has been publicly done.
CNN has tested its own ideas, and there's been talk of reviving some version of its old "Crossfire" political debate show, which was a template for opinionated talk on cable in the 1990s. CNN canceled the series soon after Comedy Central's Jon Stewart ridiculed it. One segment that has appeared on Brown's show features Mary Matalin and Roland Martin in a political debate, an idea that could potentially be expanded.
Brown, who is leaving CNN entirely, noted in a statement her "indomitable" rivals on the other networks.
"Shedding my own journalistic skin to try to inhabit the kind of persona that might co-exist in that lineup is simply impossible for me," she said. "It is not who I am or who I want to be, nor is it who CNN asked me to be at any point. This is the right decision for me and I hope it will be a great opportunity for CNN."
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