New top story from Time: Joe Biden Wins South Carolina, and Rides Into Super Tuesday as Bernie Sanders’ Chief Rival

Backed overwhelmingly by African American voters, former Vice President Joe Biden sweeping victory in South Carolina’s Democratic presidential primary on Saturday has made him the leading alternative to frontrunner Sen. Bernie Sanders on Super Tuesday and put fresh pressure on other contenders to drop out.

It is just as Biden’s campaign promised after a disappointing fourth-place finish in Iowa and an even worse fifth place in New Hampshire: When the election moved to more diverse states, Biden started to fare better, starting with a second-place finish in Nevada, and now a decisive win in South Carolina.

Biden’s triumph in South Carolina, years in the making, was the first time he has won a contest outside his home state of Delaware in his three runs for the Democrats’ presidential nomination. It was a show of grit and grind, made possible in no small measure by the endorsement of the state’s longtime kingmaker, Rep. James Clyburn, earlier in the week. More than half of South Carolinians said Clyburn’s backing was an important factor in their vote, according to exit polls, and black voters chose Biden over Sanders by a 4-to-1 margin.

But Clyburn was also pragmatic about the prospects of his old friend, who struggled to meet expectations in this race once voting began. “We will have to sit down and get serious about how we retool this campaign,” he said in a CNN interview on Saturday. The campaign announced Clyburn will go to North Carolina on Sunday to help the campaign regroup there.

They will have to act fast. On Tuesday, 14 states from Maine to California vote, plus Guam and Democrats living abroad, and Sanders is expected to come out of the mega contest swinging. That means to stay in the game, Biden will have to dominate the other Southern states voting next week, and continue to keep putting away enough cash to keep going through a marathon calendar with several other important contests coming up in March.

“Thanks to all of you, the heart of the Democratic Party, we just won, and we won big,” Biden said in South Carolina, hours after he dipped into North Carolina, which votes on Super Tuesday, for his own campaign rally. “The decisions that Democrats make all across America in the next few days will determine what this party stands for, what we believe and what we can get done.”

The pro-Biden super PAC added cash to some of the Southern states that are up on Super Tuesday: North Carolina, Alabama, Arkansas, Tennessee and Virginia, plus Texas. Biden has basic operations in those states and is now scrambling to build operations in states that vote on March 10, particularly places that may be ideological matches for his working-class message like Michigan and Missouri and conservative states where Sanders’ progressive message may be a poor fit like Idaho, Mississippi and North Dakota. If the race comes down to delegates, Biden is working to pick up victories in places where the electorate may be inclined to reject Sanders’ agenda, or places where the electorate is more diverse. Separately, an anti-Sanders super PAC has booked $2.6 million in digital ads for Super Tuesday states.

Saturday’s contest now leaves Senators Elizabeth Warren and Amy Klobuchar, as well as former South Bend, Ind., Mayor Pete Buttigieg, fighting for relevance. Each has failed to demonstrate that they can build the kind of broad coalition Democrats will need in November, including voters of color. Pressure from party insiders, activists and donors will now intensify for them to exit the race, lest a fractured field of contenders will arrive in the Democratic Convention in Milwaukee this summer without a settled nominee. Warren and Klobuchar will vote in their home states on Tuesday and are favored to add to their delegate tally. But catching up to Sanders and Biden might now be impossible for any of the three.

Meanwhile, Mike Bloomberg, the media mogul and former Mayor of New York City, has been dumping piles of cash into states that start voting on Super Tuesday. Bloomberg entered the race too late to compete in the traditional early-nominating states so his shotgun start comes in just a few days. With Sanders leading the delegates and Biden with a rush of momentum behind him, it’s unclear whether Bloomberg will be able to put up roadblocks to both candidates. Another billionaire, Tom Steyer, had opened his checkbook wantonly in South Carolina, but struck out at the polls and then dropped out Saturday evening.

That’s not to say Biden’s path will be an easy one. He hasn’t faced a real pile-on since a very bad September debate, when he was polling as the clear frontrunner in the upcoming race. It’s not clear whether anti-Sanders Democrats would spare him in next Sunday’s debate and in advertising; Biden may be their only hope of derailing the Vermont Senator, who is a self-described Democratic Socialist. The easiest path to move from the bottom tier to the top is to knock someone down, but that tactic could end up souring voters who are simply seeking any alternative to Sanders.

Sanders’ appeal is undeniable among his fervent and very-online supporters, but many Democrats rightly caution that Twitter is not reality. Centrist and establishment Democrats have spent weeks warning that a Sanders nomination would translate into a guaranteed loss against President Donald Trump’s re-election. Clyburn went so far as to invoke George McGovern: a liberal favorite who didn’t appeal widely in his party — let alone in his country — who went on to lose 49 states in President Richard Nixon’s 1972 re-election bid. Biden is leaning into that rhetoric. “We have the option to win big or lose big,” he said, celebrating with his supporters at the University of South Carolina on Saturday. “That’s the choice.”

The Biden campaign is sharpening its attacks on Sanders as someone who won’t stand up to the National Rifle Association and on Bloomberg as having been insufficiently supportive of the Obama-Biden campaigns. In an effort to cast the pair as uninvited interlopers in the Democratic primary, Biden read the teleprompter carefully Saturday night at his victory party. “If the Democrats want a nominee who is a Democrat…” he said to loud cheers, as the audience remembered that Sanders serves in the Senate as an independent and only has identified as a Democrat when he is seeking the party’s nomination and Bloomberg is a former Republican. “I’m a proud Democrat! An Obama-Biden Democrat!”

It’s a simple line. But as Democrats beyond the first four states start to weigh in, it’s one that may prove devastating to both Sanders and Bloomberg. Now, with clear standing as the leading alternative to both, Biden is riding it into Super Tuesday with new credibility. His will be a challenge to deliver that sharpened message to open ears, to build a campaign machine in upcoming states in short order and to keep the cash flowing. Given his confidence — and success — this week, Biden isn’t one to be ruled out.