If you thought the so-called 527's and the swiftboating of John Kerry in 2004 was bad, wait until you find out about the new outlet for political soft money. Remember McCain-Feingold? Well, now a group of McCain supporters are leading the charge.

The group running the commercial in South Carolina is registered as a 501(c)(4) nonprofit corporation. As such, it is allowed to raise and spend unlimited amounts from individuals without any disclosure, as long as it can argue that it is more concerned with the promotion of an issue — like the final passage of the Wounded Warriors bill — than the election of a candidate.

The lack of disclosure makes it hard to tell how the group spends its money, and impossible to say where it gets its money, and whether its donors have already donated directly to candidates.

The group was started by Rick Reed, whose firm helped produce the 2004 Swift Boat advertisements that questioned Senator John Kerry’s war record in a way that Democrats, and even Mr. McCain, said was unfair — but, also, in a way that both sides agree did great damage to Mr. Kerry’s presidential campaign. Mr. Reed is also a long-time strategist for Mr. McCain, working for his 2000 presidential campaign and briefly for his 2008 campaign, before it ran short on money and trimmed its operations.

The group is running its first advertisements in a crucial early voting state, South Carolina, just as Mr. McCain’s campaign is poised to accept federal matching funds and thus internal spending limits. Mr. McCain was badly beaten in the state in 2000.

Mr. McCain immediately called on the group to cease its activities when its existence was first reported, by The Associated Press, on Friday. Mr. McCain said on Fox News Sunday that he had not spoken to Mr. Reed to ask him to do so directly.

“I have not called Rick Reed because I don’t know what his involvement is,” Mr. McCain said. “I have condemned those ads.”

Mr. McCain’s opponents have called his condemnation disingenuous. Referring to the 2002 campaign finance law that Mr. McCain sponsored with Senator Russ Feingold, Democrat of Wisconsin, a spokesman for Mitt Romney, Kevin Madden, said, “Isn’t it ironic that the author and champion of the McCain-Feingold campaign finance reform bill now has a soft-money effort created on his behalf?”