MANCHESTER, N.H. – Former Vice President Joe Biden, coming off a lackluster fourth-place finish in Iowa and sliding in the latest polls in New Hampshire ahead of Tuesday’s primary, took aim on Saturday at rising 2020 rival Pete Buttigieg.

Speaking with reporters at a news conference at a Biden campaign field office in New Hampshire’s largest city, the former vice president vehemently disagreed with comparisons between the former South Bend, Ind., mayor and Biden’s boss for eight years, former President Barack Obama.

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“This guy’s not a Barack Obama. Barack Obama had been a United States senator of a really large state,” Biden said. “This is a very different situation.”

Biden spoke with reporters hours after his campaign went up with a new digital ad suggesting the 38-year old candidate -- who’s four decades younger than Biden -- doesn’t have enough experience to be president.

The spot uses a clip of then-President Obama calling Biden “the best vice president America’s ever had” before going on to compare crucial successes of the Obama administration with mundane mayoral actions by Buttigieg, such as installing “decorative lights under bridges.”

The Buttigieg campaign, as well as a number of mayors who’ve endorsed Buttigieg, decried the ad.

Buttigieg’s gaining moment waso beating expectations in Iowa after he tied Sen. Bernie Sanders, as the results dribbled in the days after Monday’s caucuses due to a technical reporting debacle.

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Buttigieg has repeatedly emphasized his outside-the-Beltway experience, and his campaign spotlighted that while “Washington politics trivializes what goes on in communities like South Bend, South Bend residents who now have better jobs, rising income and new life in their city don't think their lives are a Washington politician's punchline.”

And the campaign argued that the “Vice President’s decision to run this ad speaks more to where he currently stands in this race than it does about Pete’s perspective as a mayor and veteran.”

Asked about his campaign’s digital video, Biden explained: “What I’m doing is responding to what Pete’s been saying for the last two months, that all the problems we have today are from the recent past.”

“When you get attacked, you have to respond. I kept my mouth shut for a long time. I haven’t responded at all. But it’s been constant, a constant assertion that the problems we’re facing today are somehow because of our administration. That’s simply not true,” Biden said.

And jabbing at Buttigieg, the former vice president said: “He’s a good guy. He was a great mayor. But he was a mayor. He was a good guy. But the idea of passing a budget as mayor of a town the size of Manchester and managing $900 billion with less than one percent fraud or abuse, and picking up his city and thousands of cities across the country, is ridiculous.

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Biden seemed to downplay expectations in New Hampshire, which holds the first primary in the White House race, at the start of Friday night’s Democratic presidential nomination debate.

“I took a hit in Iowa and I’m probably going to take a hit here,” the former vice president said at the debate, just days before the primary race.

Biden’s comments came hours after top aides also seemed to minimize the importance of New Hampshire, highlighting in a statement that “the campaign has had a very clear strategy from the day we got into the race."

"We have articulated that we believe for us the pathway to the nomination runs in particular through Nevada, South Carolina, Super Tuesday, through states that have a more diverse electorate, where Vice President Biden has a tremendous amount of support," the campaign added.

When asked by Fox News if he’s writing off New Hampshire, Biden pushed back, saying: “I’m not writing off New Hampshire. I’m going to campaign like hell here in New Hampshire, as I’m going to do in Nevada, in South Carolina and beyond. Look, this is just getting going here. This is a marathon.”

He also said that he’s best-equipped to beat President Trump in crucial Rust Belt swing states that Trump narrowly won in 2016 in capturing the White House.

“Look at the polling, what the polling data shows who can win Pennsylvania going away. Who can win in Michigan. Who can win in Florida. Come on man,” he insisted.

And taking aim at Buttigieg -- whose struggles to resonate with black voters has been well-documented -- Biden said: “You can’t win without that. Flat out. You can’t win without it.

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Biden also pointed to national polls in the Democratic nomination race, saying “I’m still winning nationally.”

Asked about his mindset, the former vice president responded that “my spirits are up. Look at all the endorsement I’ve got since Iowa.”

And seeming to downplay the delayed results from Monday’s Iowa caucuses -- due to a reporting debacle -- Biden spotlighted that “I don’t think we should be drawing a lot of conclusions from Iowa.”