I've wondered this, as have others. So far, there's been mostly radio silence, particularly from groups like the Campaign Legal Center and Democracy 21, both with deep ties to McCain, both with deep roots with the campaign finance legislation reform community, both usually quick to the draw when lawmakers attempt to interpret election laws to their advantage.
Larry Gold has attempted an answer. He has the credentials, being a litigator of McConnell v. FEC before the Supreme Court. He is a critic of McCain's.
In a two-page document he's posted on Rick Hasen's campaign law blog, he muses:
Like others, I have been awaiting with interest the analysis of these important matters from the Campaign Legal Center (CLC) and Democracy 21 (D21). CLC and D21 are ardent advocates and litigants on the ethical and legal behavior of candidates, political parties, unions, corporations and other private organizations with respect to politics and lobbying, they are often quoted by the media as objective and authoritative arbiters of such behavior, and they rely on their media relationships for their own fundraising and influence. Ordinarily, CLC and D21 would be outspoken about an imbroglio concerning a presumptive presidential nominee’s belated effort to withdraw from public financing at a time when the FEC is raising legitimate procedural and substantive questions about his doing so. And, ordinarily they would be quick to weigh in about potentially unethical contacts between a lawmaker and lobbyists and possible attempts to cover them up.
"[D]on’t CLC and D21 believe that Senator McCain is now trying to exploit a “loophole” in that system, isn’t he violating at least the “spirit” of the law, and doesn’t his current effort to withdraw from his public-funding commitment seek to “circumvent the rules”?"]
Regardless of whether McCain is doing something nefarious -- whether he's violating the spirit or letter or intent or a law, his assertions have raised the type of questions that the Campaign Legal Center and Democracy 21 usually jump into in earnest. Indeed, both groups have been vocal in urging Barack Obama to abide by the pledge he made last year to enter into the public financing system for the general election provided his opponent did so.
A spokesperson at Democracy 21 said: "We have not put out any statements."
Dave Vance, at the Campaign Legal Center, acknowledged the perceptual pressure his organization faced. Its president, Trevor Potter, is McCain's general counsel. Mr. Potter has taken a leave of absence from the group, although he "might be talking to people on behalf of fundraising," Vance said. As for McCain, "he happens to be on the same page as us for reasons for political expediency right now."
I asked Vance whether the CLC would hesitate to take a shot at McCain if he violated any of the CLC's principles.
"No," he said.
In truth, the matter is complex and turns on fairly obscure points of law that the CLC and Democracy 21 usually wouldn't be expected to master, much less to advocate for. But it's no doubt a cautionary tale for them: their critics will be watching how they respond to McCain's every interaction with campaign finance.