Maybe the conservative critics are right: A whopping 71 percent of the media narrative about Mitt Romney has been negative, a new study says.

But wait: the same report says 72 percent of the media treatment of President Obama has been negative as well.

Apparently, journalists don’t think much of either guy.

But there’s an equally striking finding in the Project for Excellence in Journalism study: the campaigns are having increasing success at circumventing the mainstream media.

Since 2000, the percentage of personal assertions about the candidates by journalists has dropped by almost half, from 50 to 27 percent. And the proportion of what Americans hear coming from the campaigns and their surrogates has jumped from 37 to 48 percent.

The news business “appears increasingly to be a conduit of partisan rhetoric and less a source than it once was of independent reporting,” says Tom Rosenstiel, the group’s director. “This may reflect the impact of shrinking newsrooms. But it probably also helps explain why the campaign feels so negative.”

Let’s take a closer look at the negative coverage, which ranges from the candidates’ character to their record. The project examined 800 stories in 50 news outlets from May 29 through Aug. 5.

For the president, the No. 1 media narrative is that his economic policies have failed. Some 36 percent of the statements about his character and record bolster that case, compared to the 16 percent that say he helped the economy.

For Romney, the top media narrative is that he’s a “vulture” capitalist who doesn’t care about workers, a sentiment that accounted for 14 percent of the statements about his character. A close second, at 13 percent: he is a wealthy elitist. Another 11 percent say he makes gaffes or lacks charisma.

So in this telling, Mr. Ineffectual is running against Mr. Moneybags.

Wait, it gets worse. According to polls cited here, 48 percent of the public either thinks Obama is a Muslim or isn’t sure, with 49 percent correctly identifying him as a Christian—worse numbers, in terms of voters not having the facts, than in 2008. There were sufficient media stories about the question that it amounted to 7 percent of the coverage, but the study notes that the discussion was evenly split, making it something of a wash.

Obviously, the coverage in part reflects the extraordinary negativity of both campaigns and their super PAC allies. But with such lopsided figures, journalists bear a significant part of the responsibility.

Have things always been this bad? John McCain’s coverage was 57 percent negative four years ago, and Obama’s 31 percent negative (yes, the spread is eye-popping even now). This election more closely resembles 2004, the study says, when George W. Bush’s media coverage was 75 percent negative and John Kerry’s 70 percent negative—in a campaign heavily influenced by the Iraq war and the Swift Boat attacks. (The figures are for personal assertions about the candidates.)

The flip side of the 2012 findings is the lack of positive attention. Just 3 percent of assertions about Obama contain the idea that he cares about ordinary Americans. Some 8 percent of the coverage did reflect the notion that Romney has the experience to fix the economy—but 10 percent refuted it.

Is all this having an impact on the electorate? No question. Favorability ratings for both candidates are at the lowest level for presidential contenders since 1992, the project says.

One last finding, which may not shock cable watchers: Fox News was 6-to-1 negative in its assessments of Obama, while MSNBC was the mirror image in its coverage of Romney. By the way, the Fox assessment of Romney was hardly glowing, with 56 percent negative assertions and 44 percent positive.

CNN’s coverage was more like the rest of the media, the project says: its master narratives were 71 percent negative toward Obama, 62 percent negative toward Romney. On the network newscasts, the figures were 42 percent negative toward the president and 29 percent negative toward his challenger.

Newspapers were more balanced but just as sour. Their coverage of Obama was 65 percent negative, and of Romney, 66 percent negative.