COLUMBIA, S.C. — Joe Biden is back.

The former vice president won the South Carolina Democratic primary in dominant fashion Saturday, establishing himself as the leading rival to the self-described democratic socialist Sen. Bernie Sanders, and reshaping the presidential race by narrowing the path forward for other center-left candidates.

“For all of those of you who have been knocked down, counted out, left behind, this is your campaign," Biden told supporters here. "Just days ago, the press and the pundits had declared this candidacy dead. Now, thanks to all of you, the heart of the Democratic Party, we just won and we won big.”

The margin of victory — he had captured almost half of the votes counted as of late Saturday night — demonstrated the breadth of his appeal in the state and awarded him enough delegates toward the nomination to move him into second place behind Sanders in that critical tally.

It was Biden’s first win in a nominating contest ever, across three White House campaigns spanning 33 years.

The victory, after dismal showings in Iowa and New Hampshire, vaulted Biden to the front of the pack among Democratic moderates heading into Super Tuesday, when 14 states will award more than one-third of the delegates needed to win the nomination.

In winning South Carolina, Biden demonstrated his strength with African American voters, a critical Democratic constituency, while opponents such as Pete Buttigieg and Sen. Amy Klobuchar struggled, pointing to the limits of their appeals. Several southern states with large black populations vote Tuesday.

Biden will hope for a repeat performance, when another slew of southern states are among those voting, and when he again hopes African American support will propel him. Biden doesn’t have the resources or field operations of his leading competitors: Sanders, the front-runner, or billionaire former New York Mayor Mike Bloomberg, who has spent millions on TV advertising across the next states to vote and will be appearing on the ballot for the first time after skipping the early contests.

The victory immediately added to the chorus of voices from moderate party figures calling for other candidates to get out of Biden’s way. Many Democrats are desperate to find someone who can coalesce moderate voters and stop Sanders, who they fear is too liberal to defeat President Donald Trump and could cost the party hard-won gains in battleground districts.

"Clearly, this is now a two-person race,” said Rep. Brendan Boyle, a Philadelphian who, like much of Pennsylvania’s Democratic establishment, supports Biden.

“If you do not have a pathway, let’s not wait until Super Tuesday,” said former Virgina Gov. Terry McAuliffe, who endorsed Biden on CNN right after the race was called for him. “If you don’t have a pathway, who is it that you think is the most electable and can help the Democratic Party from the top to the bottom in all the local races and the statewide races?”

Shortly after the race was called, billionaire Tom Steyer, who had invested heavily in South Carolina, suspended his campaign.

Biden had also invested heavily in South Carolina, spending most of the last couple of weeks campaigning here, and he was one of the only candidates who stayed in the state for the results. Sanders had moved on to Virginia, while Bloomberg and Klobuchar were in North Carolina. Buttigieg, who finished fourth in South Carolina, was in Tennessee Saturday night and Sen. Elizabeth Warren, who came in fifth, delivered an address in Houston.

“There are a lot of states in this country. Nobody wins 'em all,” Sanders said at a rally in Norfolk, Va. He touted his earlier wins in New Hampshire and Nevada, and popular-vote victory in Iowa.

With Biden declared the winner immediately after polls closed, the crowd at the University of South Carolina’s volleyball center here broke into a dance party. MSNBC flashed results of Biden with a huge lead, and Lorenza Breedlove let out a “Go Joe!” Breedlove, 67, a retired insurance agent, said “this was exactly what he needed. If he can carry this energy, he’s got it.”

Breedlove said a late endorsement by the influential Rep. Jim Clyburn provided a huge push for Biden, something exit polls confirmed. “It moved a lot of people off the fence, hesaid, adding: "I was never on the fence. Joe was always my man.”

In his introduction of Biden, Clyburn called him “a real good man."

Clyburn said “people were confusing goodness with weakness. ... You don’t have to be bombastic in order to get your point across. You don’t have to call people names in order to get your position understood.”

Biden harkened back to that in his victory speech. “This multiethnic country we call our democracy can’t survive unless we focus on our goodness,” he said. “We can build a more perfect union. The American people have seen the alternative.”

It was African American voters, who make up about 60% of the Democratic primary electorate in the state, who revived Biden’s bid for the presidency at a critical moment.

“I think there are people who underestimate what Joe Biden means to South Carolina and how people view him in South Carolina,” said Fletcher Smith, a former state representative and Biden consultant. “And I think it extends beyond South Carolina to Super Tuesday’s southern states, where there’s a strong rural presence but also the flirtation of urban and suburban-ness.”

Smith predicted there will be fractures within the African American community — as there appeared to be in South Carolina, with older and younger black voters split on Biden. “I think in the end Joe Biden is poised to do well [with black voters] and so will, in all honesty, Bernie Sanders and Michael Bloomberg,” Smith said.

With several additional southern states set to vote just days later, many with similarly large African American populations, Biden’s win could reorder the race by dooming rival moderates such as Klobuchar and former Mayor Pete Buttigieg of South Bend, Ind., who have failed to gain much support from people of color, a key part of the Democratic coalition.

“This thing could narrow down very quickly to a race between Bernie Sanders and Joe Biden,” said David Axelrod, a former top strategist to President Barack Obama.

South Carolina could signal good things for Biden in states with similar electorates like Texas, North Carolina, Virginia, Tennessee, Alabama, Oklahoma and Arkansas — all voting Tuesday.

Bloomberg campaign manager Kevin Sheekey signaled Saturday night that the Republican turned Democrat would remain in the race at least through Tuesday’s coast-to-coast contests."Mike Bloomberg has not been on the ballot yet," Sheekey said in a statement.

At the polls Saturday in Columbia, Tonya Arthur, 49, said she voted for Biden because, “We know him here. And I think he has the best chance about Trump, I hope so anyway.”

“I think he understands middle-class people," Arthur said. "I think he’s got a pretty good chance if people get out and vote.”

After Biden’s victory party, Eddie Walker had to drive back to Georgia. She’ll vote in her home state on March 24, but wanted to come to the party 130 miles away.

She thinks Georgia, and other southern Super Tuesday states, will follow South Carolina’s lead.

“No question,” she said. “We’re claiming it now."