Seen the oily (and, admit it, funny) ad about North Carolina's Sen. Richard Burr and his coffer-filling corporate buds?

Well, Sen. Bur calls the current ad — paid for by the League of Conservation Voters, VoteVets.org Action Fund, the Sierra Club and the Service Employees International Union — "gutter politics" and claims their attempts at "character assassination" won't work.

Of course, he's not denying the truth: He did accept nearly half a million dollars from oil companies. But, I guess that's non-gutter politics in his book. Suppose that depends on who you ask.

Here's the latest oily ad, and a couple more for good measure: