The LATimes' James Rainey writes that despite getting more airtime (166 minutes of coverage in the seven weeks after the end of the primary season for Obama, vs. 67 minutes for McCain) the broadcast networks have been tougher on the democratic candidate than the republican candidate.

The Center for Media and Public Affairs at George Mason University, where researchers have tracked network news content for two decades, found that ABC, NBC and CBS were tougher on Obama than McCain during the first six weeks of the general-election campaign...28% of the statements were positive for Obama and 72% negative. Network reporting also tilted against McCain, but far less dramatically, with 43% of the statements positive and 57% negative, according to the Washington-based media center.

"This information should blow away this silly assumption that more coverage is always better coverage," said Robert Lichter, director of the center.

Still Rainey observes, "don't expect cable talking heads to end their trashing of the networks."

Repeated assertions that the networks are in the tank for Democrats represent not only an article of faith on Fox, but a crucial piece of branding. On Thursday night, [Bill] O'Reilly and his trusty lieutenant Bernard Goldberg worked themselves into righteous indignation — again — about the liberal bias they knew was lurking. Goldberg seemed gleeful beyond measure in saying that "they're fiddling while their ratings are burning." O'Reilly assured viewers that "the folks" — whom he claims to treasure far more than effete network executives do — "understand what's happening."