POLITICAL gurus Neil Oxman, J.J. Balaban and the Campaign Group have marked their territory - again.

They've created what is the most effective campaign commercial of the season. And if Joe Sestak defies the odds and a hostile electoral climate for Democrats to win election to the Senate, he'll be the latest politician to owe them a massive thank-you. He should also give his dog a bone.

"My family loves Belle," Sestak says in the new ad. "But she can make a mess and we have to clean it up." He didn't want to bail out the banks, he confesses, but needed to in order to forge a recovery from "the mess left behind" by George W. Bush and his opponent in the Senate race. "They let Wall Street run wild. Now Pat Toomey is attacking me for cleaning up his mess."

With that last line, Sestak deposits a bag of Belle's brownies into the trash.

I ASKED the creator of the ad, J.J. Balaban, his thinking behind the spot.

"One of the things that I've seen resonate when Joe is out talking with people is how his first job in the Navy was damage-control officer on the USS Richard E. Byrd and how he sees parallels between that and what he's done in Congress when he arrived at the end of the Bush years," Balaban told me.

"That got Joe and I thinking about how to explain what it has been like to have to clean up the mess left by Bush and Toomey."

Makes sense. Some might see it as too busy and a little defensive. It does require Sestak to acknowledge his vote for the unpopular bank bailout.

Still, it's no surprise that in the days after "Belle" hit the airwaves, a Muhlenberg College/Allentown Morning Call survey found Sestak ahead by three points. Even Toomey's campaign manager, Mark Harris, acknowledged that the race has gotten noticeably tighter.

"This is going to be a close race to the end and we just have to keep fighting," he said this week. "Anyone who expected a Republican Senate candidate to win by 10 or 12 points in Pennsylvania was somewhat naive."

If it works, it won't be the first time Oxman's team has pulled a candidate out of the doghouse.

In 2007, it was the famous "Olivia" spot, which humanized the wonky Michael Nutter and pushed him to the top of a crowded heap of mayoral hopefuls in Philadelphia.

And earlier this year, it was the devastating "re-

e-LEC-ted" ad that propelled Sestak past Arlen Specter in the Democratic primary.

Now, the Campaign Group's handy work in the alternately delightful and disgusting "Belle" ad seems to have finally moved numbers for the Democrat in the race to replace Pennsylvania's longest-serving U.S. senator.

The "Belle" spot has two things going for it.

For one thing, dogs are always a safe bet - no matter what realm they wander into. That's especially true in Pennsylvania, which, given the Eagles' signing of Michael Vick and the state's campaign against inhumane dog kennels, is especially sensitive to man's best friend.

But most impressive is that it stands out in a torrent of spots that are hard to escape. That deluge is even more overwhelming this year in the wake of the Supreme Court's ruling in the Citizens United case, which essentially has allowed corporations and unions to advocate for or against candidates all the way up to Election Day.

And as a result, the seemingly endless array of political ads has been even more mind-numbing than usual. "This candidate" wants to return the country to the failed policies of George W. Bush. "That candidate" voted for bank bailouts and health-care reform. I doubt most voters can accurately recall any ad.

And rare is the spot that leaves any impression other than boredom.

With "Belle," Sestak has managed to get voters' attention. That alone makes it worth the investment.

And if it proves to turn the momentum in Sestak's favor in time to pull off the ultimate political coup, he'll have Pennsylvania's most accomplished political gurus - and Belle - to thank for it.

Listen to Michael Smerconish weekdays 5-9 a.m. on the Big Talker, 1210/AM. Read him Sundays in the Inquirer. Contact him via the Web at www.smerconish.com.