MANCHESTER, N.H. - Democratic White House hopefuls Bernie Sanders and Pete Buttigieg — neck-and-neck in the polls ahead of the next primary contest — clashed in an animated debate Friday over what path the party should take to beat President Donald Trump.

Buttigieg, a former mayor of South Bend, Indiana, who at 38 is a fresh face on the national stage, defended himself against charges of inexperience and in a dig at Sanders urged Americans to elevate a nominee who will “leave the politics of the past in the past.”

The 78-year-old leftist Sanders, eyeing the moderate Buttigieg as his possible chief adversary, aimed his own shots at his far younger rival on the debate stage in Manchester, New Hampshire, casting him as the candidate of Wall Street.

“I don’t have 40 billionaires, Pete, contributing to my campaign,” Sanders said.

Democratic presidential candidates former Vice President Joe Biden, left, and Sen. Bernie Sanders (I-VT) participate in the Democratic presidential primary debate at St. Anselm College, Feb. 7, 2020, in Manchester, N.H.

Sanders’ policies under fire

Buttigieg and Sanders finished atop the pack earlier this week in Iowa’s chaotic caucuses, and both hope to renew the performance Tuesday in New Hampshire, as the Democratic Party seeks to pick a challenger to Trump in November.

But Sanders, a veteran senator seeking to launch a political revolution, was in the firing line from several other rivals, including former vice president and fellow septuagenarian Joe Biden, branding his policies too radical to unite Americans.

The 77-year-old Biden, fighting to keep his White House hopes alive after finishing fourth in Iowa, insisted liberal policies like Sanders’ flagship universal health care plan would be too divisive, expensive and difficult to get through Congress.

“I busted my neck getting Obamacare passed, getting every Democratic vote. I know how hard it is,” he said.

Democratic presidential candidates former South Bend, Indiana Mayor Pete Buttigieg, left, Sen. Elizabeth Warren (D-MA) and former Vice President Joe Biden participate in the Democratic presidential primary debate, Feb. 7, 2020, in Manchester, N.H.

Biden comes out swinging

Biden performed more aggressively than in previous showings, seizing a chance to argue that today’s global tensions required an experienced senior statesman to guide the nation out of a dark period.

Despite the Iowa setback he also made plain he still views himself as best placed to mount a centrist challenge to the Republican Trump, who this week survived an impeachment trial that did little to dent his electoral support.

“Mayor Buttigieg is a great guy (and) a patriot,” Biden acknowledged.

But as a mayor of a small city he “has not demonstrated his ability to — we’ll soon find out — to get a broad spectrum of support” from American voters.

A national unknown one year ago, Buttigieg’s ambitious campaign has resonated with voters who appreciate his articulate explanations of policy.

Rivals argue he is an untested newcomer on the world stage, but in Manchester he once again drew on his experience as a military veteran to seek to cast himself as a credible commander-in-chief.

And he advanced his central argument for generational change as the best way to take on society’s and the economy’s new challenges.

“The biggest risk we could take at a time like this would be to go up against the fundamentally new challenge by trying to fall back on the familiar,” Buttigieg said.

Democratic presidential candidates Sen. Elizabeth Warren (D-MA), left, and Sen. Amy Klobuchar (D-MN) greet each before the start of the Democratic presidential primary debate, Feb. 7, 2020, in Manchester, N.H.

‘Trump’s worst nightmare’

Also on the stage in New Hampshire were senators Elizabeth Warren and Amy Klobuchar, technology entrepreneur Andrew Yang and billionaire activist Tom Steyer.

Klobuchar, a pragmatist from Minnesota, put in a forceful performance as she voiced her opposition to liberal colleagues Sanders and Warren, arguing that their plans to fundamentally change the U.S. economy would turn off voters.

“I think we are not going to out-divide the divider in chief,” she said. “Truthfully, Donald Trump’s worst nightmare is a candidate that will bring people in from the middle.”

Biden appeared more energetic than usual on stage, although from the outset he embraced a stance he has rarely had in recent decades: underdog.

“I took the hit in Iowa and I’ll probably take it here,” Biden said, in an apparent recognition that Sanders is likely to win New Hampshire, the state that borders his home state of Vermont.

As the seven clashed in the debate, another candidate loomed in the background.

Former New York Mayor Michael Bloomberg chose to ignore the early nominating contests and has spent heavily on advertising, hoping to make a splash March 3 on “Super Tuesday,” when 14 states hold primaries.

After New Hampshire, the candidates turn their sights on Nevada, Feb. 22, South Carolina, Feb. 29 and then Super Tuesday.