Okay, this McCain-Soros story just keeps on giving.

McCain sent out a fundraising letter yesterday attacking a planned third-party Dem effort because it's being funded by George Soros, a reliable villain for many on the right. But as I reported below, a group that McCain co-chaired also was perfectly happy to benefit from Soros' generosity.

The group, a good-government outfit called the Reform Institute, received $150,000 from Soros in 2003 -- when McCain was its honorary co-chair and McCain's current campaign manager (the same guy who signed yesterday's fund-raising letter) was its president.

But it gets still better.

I've now learned that in 2002, Soros' charitable foundation, the Open Society Institute, gave $300,000 in grants to various groups that were defending the Arizona senator's campaign finance law against legal challenges to it.

An OSI spokesperson, Laura Silber, confirms to me that Soros' foundation gave $300,000 to the Brennan Center specifically for use defending McCain-Feingold. Brennan subsequently distributed that sum to various groups fighting on behalf of the McCain-sponsored law.

So by my count, Soros has contributed a total of $450,000 either to a group co-chaired by McCain or to defending McCain's pet legislation.

There was nothing wrong with Soros' money then, presumably. Yet now the McCain campaign is attacking a fledgling Dem effort because it's taking money from...Soros.

Doesn't get more mavericky than that.

Asked to comment, McCain spokesperson Brian Rogers emails: "This just in: George Soros' charitable foundation gave money to push campaign finance reform, the spirit of which he’s now clearly violating with a $40 million partisan attack ad campaign."