The next head to roll at CNN will be John King‘s, insiders say. “Since King replaced Lou Dobbs, he’s lost more than half his audience,” one source told us. “If it were a fight, it would be stopped on a TKO because of the bleeding.” In April, Washington Post TV critic Tom Shales quoted a producer as saying King’s show was attracting “only friends and relatives.” An insider said CNN brass are fretting because King’s anemic lead-in doomed the 8 p.m. show of Campbell Brown, who’s leaving at the end of the month and will be replaced after Labor Day by Eliot Spitzer and Kathleen Parker. King is said to have a high opinion of himself, and “the high-fives are rattling the windows on Capitol Hill,” laughed a source. A CNN rep said of King’s possible ouster, “Not true.” Wolf Blitzer will add King’s 7 p.m. hour, a source predicted. No replacement for Larry King at 9 p.m. has been named, but we’ve reported it will be Piers Morgan.