Bill Clinton in McCain ad leading role

Fancy that. The Republican presidential nominee with a tip of the hat to the last Democratic president.

A new minute-long McCain commercial features the former president asserting that congressional Democrats could have done more to regulate the nation's major mortgage financiers.

In a clip taken from a Sept. 25 interview on ABC's "Good Morning America," Clinton says: "I think the responsibility that the Democrats have may rest more in resisting any efforts by Republicans in the Congress, or by me when I was president, to put some standards and tighten up a little on Fannie Mae and Freddie Mac."

The ad is one of a flurry of commercials with economic themes that emerged Tuesday as Congress continued to struggle with a rescue plan for tanking financial markets. Obama released a new two-minute commercial denouncing the tax policies of the past eight years, and the Republican National Committee went on the air with $5 million worth of air time in Indiana, Michigan, Ohio, Pennsylvania, Virginia and Wisconsin.

The McCain ad casts the Arizona senator as an advocate of tighter regulation on Fannie Mae and Freddie Mac. That assertion is true. McCain was a co-sponsor of legislation in 2006 that would have placed more restrictions on the mortgage finance companies.

Though not shown in the ad, Clinton goes on in the interview to blame a decision by the Securities and Exchange Commission to do away with a rule that restricted short selling.

"The biggest mistake, by the way, that contributed to the current circumstance that almost nobody talks about is the repeal, after decades, of something called the uptick rule, which allows the hedge funds, heavily leveraged and others, to just drive down the market without any kind of automatic stoppers," Clinton said.

While too complicated to pitch in an ad, that view also seems to support McCain. The Republican candidate has called on SEC chairman Christopher Cox to resign.

Indeed, the Clinton interview holds several nuggets that McCain can savor.