by Evie Stone

The McCain campaign has released this new ad, featuring a former Hillary Clinton supporter saying she now supports McCain because "now he's the one with experience and judgment." The ad does not mention Barack Obama by name.

It's the third McCain ad in as many days, and the second that directly targets former Clinton voters. McCain has reason to see an opening with the Clintonites, given this data from a new CNN/Opinion Research Poll:

Sixty-six percent of Clinton supporters — registered Democrats who want Clinton as the nominee — are now backing Obama. That's down from 75 percent in the end of June. Twenty-seven percent of them now say they'll support McCain, up from 16 percent in late June.

The RNC is working the Hillary angle as well, with plans in the works for a Clinton supporters' happy hour in Denver tonight.

Clinton herself has disavowed the ads, telling a breakfast for the New York delegation in Denver this morning "I am Hillary Clinton, and I do not approve of that message."

Nonethless, one surefire way for McCain to break through the media noise surrounding the Democratic convention is with buzzworthy ads that will be played over and over on the news networks. These Hillary spots fit that description.

And don't forget that McCain has to burn through a pile of money before his public financing kicks in after next week's GOP convention. So there's no reason not to go for broke with the advertising now.

The Obama camp's task: to convince those disaffected Clinton supporters that a protest vote for McCain runs counter to their principles — especially targeting those who feel Clinton was treated unfairly because she's a woman. Look for the keyword 'Supreme Court'. Newly minted VP candidate Joe Biden will be a natural for that job, given his former Judiciary Committee Chairmanship and strong record on women's issues.