Even the liberal fact-checkers are noticing:
“There’s so much deceit here we hardly know where to start,” explains Brooks Jackson at FactCheck.org, which is run by Annenberg Public Policy Center. He’s commenting on a new [Obama campaign] ad that strongly suggests Romney committed tax fraud. “It wasn’t Romney who was avoiding taxes, it was Marriott Corp. And there’s no evidence to support the ad’s speculation that Romney himself paid no income tax, or that he did something illegal,” Jackson had already noted.
Jackson also noted that the central claims of the ad are attributed to CNN, with only the fine print acknowledging that it was an opinion piece.