Chris Matthews can't get enough of John Edwards' brutal-but-funny anti-Hillary ad, playing it twice during this evening's "Hardball." Set to the Blue Danube Waltz and based on clips from last week's debate, the theme is Hillary's double-talk on Iraq, Social Security and immigration [her triple-toe loop on driver's licenses for illegal immigrants].

But in the three-cushion game that is presidential billiards, two of Chris's guests surmised that the ad, in taking down Hillary, would likely redound to Barack Obama's benefit.

View video here [includes the Edwards' ad].

Matthews had already played the ad earlier in the show. But it didn't take much to entice him to play it again during the subsequent roundtable with WaPo's Chris Cillizza, Jill Zuckman of the Chicago Tribune, and Jennifer Donahue, political director of the New Hampshire Institute of Politics [who is quickly becoming my favorite new face on the presidential punditry scene].

JENNIFER DONAHUE: The Edwards parsing YouTube video . . . hits Clinton where she's most vulnerable, showing her flip-flopping, showing double-talk, as he calls it --

CHRIS MATTHEWS: I can't resist: Jennifer, you've done it, you've cued it one more time. I have to tell you, this is the funniest ad. It's Johann Strauss, the Blue Danube, and here it is: Hillary Clinton, caught in the act.

Matthews proceeded to play the ad. In the ensuing discussion, there was consensus that Obama might well emerge as its beneficiary.

DONAHUE: I think it's hilarious, and I think it's actually that middle road that doesn't really turn people off but that points out her vulnerabilities with humor. It's hitting her where it hurts her the most. Because Bill Clinton, and Hillary Clinton, if there's one thing that she's going to be vulnerable on, it's parsing, it's dishonesty, its double-talk. He is taking the gloves off -- and it's helping Obama too.

A bit later, Donahue added this incisive bit of analysis: "Make no mistake about it: Hillary Clinton is a candidate of convenience for the Democrats. If she looks weak, they will flee to whoever they think can beat a Republican."

Later still, Cillizza amplified Donahue's notion that Obama stands to benefit from Edwards' attacks.

CHRIS CILLIZZA: I actually think that John Edwards is doing Barack Obama a big favor. John Edwards -- and I've thought that for a while -- is better articulating the anti-Clinton message than Barack Obama is. But because of the financial, the organizational advantage that Obama and Clint have, it may wind up accruing to Obama's benefit anyway. Edwards is taking all these shots at her, scoring all these punches, but in the end it weakens her so Obama can beat her, not Edwards. It's an interesting sort of three-way dynamic.

Question: The Writers Guild strike being upon us makes me wonder: does Edwards owe residuals to . . . George Bush? Edwards ripped off the Strauss waltz theme from W's 2004 devastating 2004 Kerry windsurfing ad.

—Mark Finkelstein is a NewsBusters contributing editor and host of Right Angle. Contact him at mark@gunhill.net.