Comments made by sources, voters, reporters and anchors that aired on ABC, CBS and NBC evening newscasts over the past two months reflected positively on Obama in 65 percent of cases, compared to 31 percent of cases with regards to McCain, according to the Center for Media and Public Affairs.
ABC's "World News" had more balance than NBC's "Nightly News" or the "CBS Evening News," the group said.
Meanwhile, the first half of Fox News Channel's "Special Report" with Brit Hume showed more balance than any of the network broadcasters, although it was dominated by negative evaluations of both campaigns. The center didn't evaluate programs on CNN or MSNBC.
"For whatever reason, the media are portraying Barack Obama as a better choice for president than John McCain," said Robert Lichter, a George Mason University professor and head of the center. "If you watch the evening news, you'd think you should vote for Obama."
The center analyzed 979 separate news stories shown between Aug. 23 and Oct. 24, and excluded evaluations based on the campaign horse race, including mention of how the candidates were doing in polls. For instance, when a voter was interviewed on CBS Oct. 14 saying he thought Obama brought a freshness to Washington, that was chalked up as a pro-Obama comment.
When NBC's Andrea Mitchell reported Oct. 1 that some conservatives say that Sarah Palin is not ready for prime-time, that's marked in the negative column for McCain.
ABC recorded 57 percent favorable comments toward the Democrats, and 42 percent positive for the Republicans. NBC had 56 percent positive for the Democrats, 16 percent for the Republicans. CBS had 73 percent positive (Obama), versus 31 percent (McCain).
Hume's telecast had 39 percent favorable comments for McCain and 28 percent positive for the Democratic ticket.
It was the second study in two weeks to remark upon negative coverage for the McCain-Palin ticket. The Project for Excellence in Journalism concluded last week that McCain's coverage has been overwhelmingly negative since the conventions ended, while Obama's has been more mixed.
Meanwhile, another survey issued Friday by the Pew Research Center for the People & the Press showed that television continues to be Americans' main source for campaign news, particularly the cable news networks.
But there were clear partisan differences in where people turned.
For instance, of the people who said they got most of their campaign news from Fox News Channel, 52 percent identified themselves as Republican, 17 percent as Democrats and 30 percent as independents, the Pew center said.
MSNBC viewers interested in campaign news identified themselves at 11 percent Republican, 50 percent Democratic and 36 percent independent. The breakdown for CNN: 13 percent Republican, 45 percent Democrat, 38 percent independent.
The study was based on a survey of 2,011 people taken Oct. 17-20 and 24-27. It has a margin of error of plus or minus 2.5 percent.