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While Vice President Biden left no question Thursday night he's the attack dog on the Democratic ticket, the verdict is out whether his aggressive -- often disdainful -- debate style against Republican running mate Paul Ryan will stem the dramatic erosion in the polls of President Obama's once-solid lead.

Biden worked hard to convince the base that the Democratic team will fight for their beliefs, an impression Obama by most accounts did not leave last week. But his incessant interruptions, chuckles and snickers undermined some of the effectiveness of his attacks, analysts on both sides of the aisle said afterward.

Democratic strategist Joe Trippi said it "diminished" an otherwise strong performance.

"I thought it was really disrespectful to the American people," Romeny adviser Ed Gillespie told Fox News.

The debate may have served simply to hold the race steady, in what appears to be a dead heat. Both sides emerged claiming victory, which was a change from last week when Democrats openly acknowledged being walloped.

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It once again puts the pressure on Obama and Romney to bring a polished and presidential performance to the stage next Tuesday, at a town hall-style debate that will focus on both domestic and foreign policy.

If nothing else, the debate Thursday was historic in its feistiness. And it was the vice president who set the aggressive tone, unabashedly striving to hit reset after Obama was panned for his lackluster performance.

Biden went after the Romney-Ryan ticket with a directness that Obama did not. Notably, he hammered Romney over his secretly videotaped comment in which he said he doesn't have to worry about the "47 percent" of Americans who don't pay federal income taxes.

"These people are my mom and dad, the people I grew up with, my neighbors," Biden said, adding he's "had it up to here" with those kinds of comments.

Ryan shot back, in reference to Biden's tendency to make gaffes: "As the vice president very well knows ... sometimes the words don't come out of your mouth the right way."

"But I always say what I mean. And so does Romney," Biden responded.

Ryan, though, got his points in, maintaining a steady and comparatively reserved demeanor throughout, while sometimes seeming unsure how to respond to Biden's outsized intensity.

Ryan accused Obama of "projecting weakness" with his foreign policy, particularly in his response to the terror attack on the U.S. Consulate in Benghazi, Libya. At home, he accused the administration of presiding over a shoddy recovery.

"This is not what a real recovery looks like," Ryan said.

There are two more presidential debates on the calendar, and the polls have started to swing in Romney's favor. The tightening was reflected in the candidates' attitude onstage Thursday, each loath to give the other too many seconds of speech-time without a challenge.

The economy, the budget deficit and foreign policy were central. Each candidate made frequent appeals to the middle class, Biden by pledging to protect programs in the federal budget and Ryan by pledging to grow the economy for everybody.

After Obama's debate performance last week, the pressure was on Biden to recapture the momentum -- while equally on Ryan to prevent the Obama ticket from blunting Romney's surge.

Ryan referred to the weight on Biden's shoulders about mid-way through, as the two talked over each other on Medicare.

"Mr. vice president, I know you're under a lot of duress to make up for lost ground, but I think people would be better served if we don't keep interrupting each other," Ryan said.

On Medicare, Biden charged that the Republican ticket's plan would raise costs for future seniors with a de facto "voucher" system. "Their ideas are old and their ideas are bad and they eliminate the guarantee of Medicare," he said.

Ryan shot back: "They got caught with their hand in the cookie jar turning Medicare into a piggy bank for ObamaCare."

The final presidential debates will be held Oct. 16 and Oct. 22. The next one will be a town hall format focusing on a range of issues, and the last one will focus exclusively on foreign policy.