Strong South Carolina victory breathes new life into Biden's campaign Biden even leaned on the Palmetto State, calling it his "firewall."

Former Vice President Joe Biden found new life coming out of the South Carolina primary Saturday after three previous contests in Iowa, New Hampshire and Nevada had brought forth a clear front-runner in Vermont Sen. Bernie Sanders.

Biden sent a message with his projected South Carolina victory three days shy of Super Tuesday -- about his candidacy's resiliency, Sanders' weaknesses among some voters and the potential durability of the Obama legacy in 2020.

Even while coming in second place on Saturday, Sanders' streak of victories kept him on top of the delegate count as the stakes of the race reach new heights across a national map in 14 states and one territory on Tuesday.

Saturday's primary also offered an opportunity for the contenders to test their strength among black voters, a significant bloc of the Democratic electorate. In 2016, blacks made up 61% of Democratic primary voters in the state, according to ABC News exit poll results, and former Secretary of State Hillary Clinton captured 86% of their votes.

Democrats' efforts to court this key demographic didn't appear to make significant cracks in former Biden's "firewall," with the African American community. In a recent Winthrop University poll, Biden earned 31% support of black Democratic voters, down from 46% in October. Sanders more than doubled his support among African American voters in the new poll.

Still, Biden ultimately took home the victory in South Carolina -- bringing in at least 85% of the support among black voters, according to ABC News exit polls.

All times are eastern.

Here's how the night unfolded.

11:30 p.m. Biden at least 32 delegates richer as vote totals near 100%

ABC News estimates that Biden will earn at least 32 pledged delegates, and Sanders will gain at least 11 pledged delegates tonight -- leaving 11 delegates still up for grabs.

To surpass Sanders in the overall delegate race, Biden would need to secure the remaining 11 delegates.

He's performing best in the central region of the state and in Pee Dee, in the northeast.

Only three counties are still outstanding, including Beaufort, Lexington and York.

ABC News' Kendall Karson reported.

10:08 p.m. Biden, Sanders only candidates so far to win delegates

With 85% of precincts reporting, only Biden and Sanders have won delegates so far.

Only candidates who reach 15% either statewide or at the district level earn delegates, and across the congressional districts, Biden and Sanders are currently the only two candidates to have hit at least 15%. The closest, Steyer, is currently at is 14.3% in the 3rd Congressional District, one of the most conservative districts across the state, with 80% of the expected vote in.

In Charleston County, which is currently where both Pete Buttigieg and Warren are performing best, the former mayor edges out both the Massachusetts senator and Sen. Amy Klobuchar, with 13%, compared to Warren's 11% and Klobuchar's 4%, with 99% of precincts reporting.

Only 14 counties across South Carolina's 46 total have some precincts still outstanding, with 85% of the expected vote in. A number of these counties are from the central region.

ABC News' Kendall Karson reported.

9:30 p.m. Steyer ends presidential bid

Billionaire activist Tom Steyer, who spent at least $150 million on his presidential campaign, quit the race on Saturday night.

"There's no question today that this campaign, we were disappointed with where we came out," Steyer told supporters in South Carolina. "But I said if I didn't see a path to winning, that I'd suspend my campaign. And, honestly, I can't see a path."

He added, "Meeting you and the rest of the American people ... is the highlight of my life."

ABC News' Meg Cunningham reported.

8:57 p.m. Biden addresses his crowd: 'My buddy Jim Clyburn, you brought me back!'

Biden took the stage to deliver his victory speech in Columbia, South Carolina, embracing powerful Democratic Rep. Jim Clyburn, whose endorsement helped propel Biden to a wide margin of victory, according to exit polls.

About 24% of South Carolinians said that Clyburn's endorsement was an "important factor" in deciding their vote.

"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've just won and we’ve won big because of you," Biden said. "And we are very much alive."

He added, "Jim Clyburn, my friend who lifted me and this campaign on his shoulders," as he thanked the state.

ABC News' Meg Cunningham reported.

8:39 p.m. Sanders congratulates Biden from Virginia

Bernie Sanders, campaigning in Virginia, addressed a crowd amid news that he placed second in South Carolina to Joe Biden.

"We have won the New Hampshire primary. We have won the Nevada caucus. But you cannot win them all," he said. "A lot of states out there, and tonight we did not win in South Carolina. And that will not be the only defeat."

He continued, "There are a lot of states in this country, nobody wins them all. I want to congratulate Joe Biden on his victory tonight."

ABC News' Meg Cunningham reported.

7:54 p.m. Biden campaign touts best hour of fundraising

After Joe Biden's projected South Carolina primary win, his campaign reported having the best hour of fundraising since he entered the race.

Biden campaign Director of Online Fundraising Elana Firsht tweeted: "48 mins in and this is the best hour of fundraising the campaign has EVER had. The #BidenBounceBack is real. Thank you Team Joe!"

The campaign has yet to release how much has been raised.

ABC News' John Verhovek reported.

7:42 p.m. Trump weighs in on South Carolina

It didn't take long for the president, or his campaign, to weigh in on the South Carolina primary. Trump eschewed commentary on Biden, who ABC News projects will win in the state, and attacked Mike Bloomberg immediately after polls closed. He's made Bloomberg a repeated target in recent weeks, saying he should drop out of the race.

"Sleepy Joe Biden’s victory in the South Carolina Democrat Primary should be the end of Mini Mike Bloomberg’s Joke of a campaign," he tweeted. "After the worst debate performance in the history of presidential debates, Mini Mike now has Biden split up his very few voters, taking many away!"

The Trump campaign didn't even mention Biden in its response.

"Once again, President Trump is the clear winner because not one of these candidates has a chance at beating him in November," Trump 2020 campaign manager Brad Parscale said in a statement. "The President will be running on his solid record of achievement for all Americans and will wipe the floor with whichever Democrat is unlucky enough to emerge. The South Carolina results just prove what a hot mess the Democrat primaries are, as the field once again descends into chaos heading into Super Tuesday."

7:40 p.m. Biden picks up endorsement from former DNC chair

Biden got another boost Saturday night, picking up an endorsement from former Democratic National Committee Chair and former Virginia Gov. Terry McAuliffe. Virginia will be a hotly contested Super Tuesday race next week.

"I have made a decision. I'm going to endorse Joe Biden," McAuliffe told CNN. "He's coming up to Virginia. I thought long and hard about this. For me it's about beating Donald Trump and it's an electability issue. Who has the best shot at beating Donald Trump?"

McAuliffe will appear with Biden and former vice presidential candidate Tim Kaine at a rally in Norfolk, Virginia, on Sunday.

7:30 p.m. Sanders projected to finish 2nd in South Carolina

Based on an analysis of exit polls, Sen. Bernie Sanders is projected by ABC News to finish second in the South Carolina primary.

Sanders was the leader in delegates heading into South Carolina with 45.

7:10 p.m. Black voters in South Carolina prefer Biden 3-to-1 over Sanders

Joe Biden garnered more than three times the support shown to Bernie Sanders by black voters in South Carolina -- 60% to 17% -- after the former vice president racked up a 10-point margin from that electorate in Nevada.

Biden's support among black voters trumped Sanders’ customary strength among younger and more liberal voters: Blacks younger than 45 and liberal blacks, including those who described themselves as very liberal blacks, all preferred Biden in South Carolina.

Notably, too, 42% of all voters in the state, and 52% of blacks, picked Biden as the candidate who "best understands the concerns of racial and ethnic minorities." About 2 in 10 overall picked Sanders on this measure, while 1 in 10 picked Tom Steyer.

About 52% said the next president should return to Barack Obama’s policies, compared with approaches seemed more liberal (27%) or more conservative (17%). That was a boon for Biden, as 6 in 10 of those who preferred Obama-era policies backed him. Sanders won voters seeking more liberal policies, but by less of a margin.

ABC News Polling Director Gary Langer reported.

7 p.m. ABC News projects Biden to win South Carolina primary

Based an analysis of the exit polls, ABC News projects Joe Biden as the winner of the South Carolina Democratic primary.

It's his first win as a 2020 presidential candidate.

Biden has leaned on South Carolina, calling it his "firewall."

Polls in South Carolina are now closed.

ABC News' Kendall Karson reported.

6:15 p.m. Compared to New Hampshire, fewer voters in South Carolina are 'angry' about Trump

About 43% of South Carolinians are "angry" about the Trump administration, far fewer than the 79% in New Hampshire, based on preliminary exit polls.

Meanwhile, 51% of Democratic voters favor a return to Obama-era policies, though only 40% said so in New Hampshire.

ABC News Polling Director Gary Langer reported.

5:45 p.m. Health care remains top issue for voters.

Health care continues to be the top issue for voters in South Carolina.

Based on preliminary exit polls, 39% of respondents said it was their top issue, followed by income inequality, race relations and climate change.

About half support a government-run, single-payer health care system -- a good sign for Sens. Bernie Sanders and Elizabeth Warren, although that's fewer than in the previous early-voting states.

Additionally, 53% are prioritizing electability over someone who agrees with them on the most on major issues -- also fewer than in the previous states.

About 51% said that the American economic system needs "a complete overhaul," while 35% said it requires only "minor changes."

Come November, 8 in 10 primary voters said they'll vote for the Democratic nominee, whomever it is.

ABC News Polling Director Gary Langer reported.

5:30 p.m. South Carolinians say Clyburn's endorsement swayed vote

Nearly a quarter of South Carolinians say that powerful Democratic Rep. Jim Clyburn's endorsement of Biden was "the most important factor" in making their decisions, based on preliminary exit poll results.

Despite Clyburn's support of Biden, he offered strong criticisms of the former vice president's campaign strategy heading into Super Tuesday and beyond.

"We need to do some retooling in the campaign. No question about that. I did not feel free to speak out about or even deal with it inside, because I had not committed to his candidacy,” Clyburn said today on CNN. “I have now. I'm all in. And I'm not going to sit idly by and watch people mishandle his campaign.”

Biden's campaign has faced criticism over being unorganized and underfunded heading into key Super Tuesday states. Now that Clyburn has endorsed Biden, he is not being quiet about what he thinks is wrong with the campaign.

ABC News Polling Director Gary Langer and John Verhovek reported.

5:10 p.m. Preliminary numbers show Biden on the upswing

Personal popularity and a large black electorate appear to be boosting Joe Biden in South Carolina, while Bernie Sanders, the Democratic front-runner, lags in favorability and has comparatively fewer liberal voters to help replicate strong results in Iowa, New Hampshire and Nevada, preliminary numbers from ABC News show.

Biden is popular here: 75% of voters express a favorable opinion of him overall, including 84% of blacks, who compose 55% of the state’s Democratic primary voters in preliminary exit poll results. Fewer overall see the Vermont senator favorably -- around 53%, with only 57% of black voters, a group in which Sanders has struggled.

It’s also a first chance to see voters’ views of billionaire Mike Bloomberg, even though he’s not on the ballot in South Carolina. Early exit polls find that just 25% view him favorably overall. As for other top candidates, Tom Steyer, who's spent heavily in the state, is seen favorably by 55%, Sen. Elizabeth Warren by 54%, former South Bend, Indiana, Mayor Pete Buttigieg by 51% and Sen. Amy Klobuchar by 44%.

On Bloomberg, just 18% of very liberal voters see Bloomberg favorably, compared with 25% of those who are somewhat liberal and 33% of moderate Democratics. His favorability ratings are about the same among blacks and whites, men and women.

ABC News Polling Director Gary Langer reported.

4:30 p.m. Sen. Amy Klobuchar downplays expectations in South Carolina

When asked about the first-in-the-South primary, Klobuchar downplayed expectations, pivoting instead to her campaign’s plans for success in Super Tuesday states.

“I don't pretend to think I'm going to be No. 1 in South Carolina. I think we've seen that in the polls," she said. "But my point is that we are still number three in total votes and we are going to be going into the Super Tuesday states of a state like Colorado or a state like Virginia strong."

Klobuchar noted that while she's struggled to find her footing in South Carolina -- because she didn't have the operations or funding in place to score success -- she suggested that her campaign is rolling on a state-by-state basis.

“Now, at least on Super Tuesday, we're able to buy ads at a rate equivalent to many of the campaigns. We're able to have staff in all of these states," she said. "Probably no different than a lot of the other campaigns in terms of a number."

The Minnesota senator has garnered several endorsements from local newspapers in Super Tuesday states, and said she believes that will be one of many predictors of success on Tuesday.

ABC News' Arielle Mitropoulos reported.

3:45 p.m. Like Nevada, GOP canceled nominating contest in South Carolina

Republican officials in the Palmetto State voted in 2019 to cancel their nominating contest in 2020, as they did for the Nevada caucuses.

This paves the way to the GOP nomination for President Donald Trump, who will likely take home all 50 Republican-pledged delegates.

ABC News is keeping track of the delegates up for grabs in South Carolina.

3 p.m. South Carolina primary by the numbers

Voting -- from 46 counties with 2,259 precincts -- began in South Carolina's key primary at 7 a.m. on Saturday, and will continue until 7 p.m., though voters who are in line right at the end can still vote.

The Democratic contenders are vying for the 54 pledged delegates up for grabs.

After three early nominating contests, polling from ABC News' partners FiveThirtyEight has shown that only a small number of the candidates are expected to be competitive enough to receive any of the national delegates.

Make-or-break for former Vice President Joe Biden

This cycle, no one more than Biden is banking on a win in the Palmetto State, fueled by his long-standing ties to the African American community, which is considered the bedrock of his support, to reset the campaign in his favor.

South Carolina's primary is his chance for a revival after two less-than-stellar performances in Iowa and New Hampshire, and a strong performance there could allow him to come within striking distance of Sanders' delegate edge. Biden's chances were boosted Wednesday after he scored the weighty endorsement of House Majority Whip Jim Clyburn, the highest-ranking African American member of Congress and a political kingmaker in the state.

But with pressure on Biden to not only win, but also to win big, the elder statesman has been knocking his progressive rival on the trail.

"Today, people are talking about a revolution. What the country's looking for are results, what they're looking for is security, what they're looking for, is being able to sustain and maintain their dignity," Biden said at the endorsement announcement earlier this week, in an apparent swipe at Sanders' call for a "political revolution."

"I will win the African American vote here in South Carolina," he continued. "I will win South Carolina ... If you send me out of South Carolina with a victory, there will be no stopping us."

Moderate Democrats turn to down ballot races in bid to blunt Bernie Sanders' momentum

For Sanders, who faced an onslaught of attacks in the last Democratic debate in Charleston, South Carolina, when a number of his competitors questioned his viability and cast his campaign as out-of-step with down-ballot Democrats -- who won back the House in 2018 -- in part, on protecting the Affordable Care Act, South Carolina is not a must-win.

Still, the liberal stalwart, who has visited the state the most to date, is keenly aware of the gains he's made on the ground, which have allowed him to close in on Biden in more recent state polling.

"Over the last couple of months because of our great staff and our volunteer support and many of you, we have come a long, long way in closing that gap," Sanders said Wednesday, shortly after Clyburn endorsed Biden.

"Now, to defeat [President Donald] Trump, you cannot run a conventional campaign. Same old, same old is not gonna do it," he told his supporters. "Joe is a friend of mine and a decent guy, but that is not the voting record or the history that is going to excite people, bring them into the political process and beat Trump."

The Vermont senator has focused most of his efforts in recent weeks on Super Tuesday, making a number of campaign stops across the 14 states voting next week, even as the Nevada caucuses were approaching last week. This week, Sanders is holding events in South Carolina, North Carolina, Massachusetts and will also spend primary night in Virginia.

Potential rise of billionaire Tom Steyer

But the home stretch ahead of South Carolina's primary has also seen the unexpected, subtle rise of Tom Steyer, the billionaire who is spending $22.4 million to blanket the airwaves across the state, and who may be unsettling what should be a settled contest.

Steyer's disruption of the last early contest is reflected in a recent NBC News/Marist poll, in which Biden is only narrowly leading Sanders by 4 points, potentially in part because Steyer, who has aggressively campaigned across the state more recently, could be cutting into the former vice president's vote share. Steyer is currently sitting comfortably in third place, according to ABC News partner FiveThirtyEight's averages of state polling, a far better position for the former investment manager than in national polls.

In his vigorous campaign to win over black voters, a core constituency he is hoping will propel his long-shot bid forward, Steyer is relying more on his alternative appeal.

"We don't have to go with a socialist who thinks the government has to take over big parts of the economy. We don't have to go with a Republican who did stop and frisk," He told a predominantly black crowd at the National Action Network Ministers' Breakfast in North Charleston on Wednesday. "The Democrats in South Carolina, get to make a reset. It's two-thirds African Americans. That is appropriate."

Preparing the way before Super Tuesday

The other billionaire, former New York City Mayor Michael Bloomberg, is not on the ballot, part of his effort to not compete in the first four early states but formally make his entrance on the ballot on Super Tuesday.

For the rest of the field, particularly, Sens. Elizabeth Warren, D-Mass., Amy Klobuchar, D-Minn., and former South Bend, Indiana, Mayor Pete Buttigieg, who have all struggled to make inroads with black voters, a poor performance in South Carolina makes Super Tuesday all the more important.

Buttigieg has recently sought to be open about his shortcomings in fully speaking to the experiences of the black community, but he has also acknowledged the limited gains he's made with the African American community in an interview with CNN this week.

"The candidates who are doing best with black voters here have one of two things going for them: Years or decades of exposure to gain trust, or billions of dollars to run tons of advertising to make up for not having those years," he said. "I don't have that, and yet I still believe that I can make these kinds of inroads and outreach, recognizing that it's also asking for a lot."

In her closing argument in the state, Warren continued to embrace her fighting spirit, which has been reflected in her more forceful debate performances over the last two weeks.

Warren, Klobuchar make their case for staying in the race

"Right now we've got an America where if you're rich, you've got a really loud voice in Washington, but if you're not rich -- you don't get heard very much," she told supporters in Orangeburg, South Carolina, alongside singer John Legend on Wednesday. "The danger is real ... In the face of this kind of danger, are we going to back up? Are we going to get timid? Are we going to crouch down or are we going to fight back?"

She added, "Me, I'm fighting back ... fighting back is an act of patriotism."

For Klobuchar, in one of her last South Carolina events for the week, she pitched herself as the one who can bring more voters into the party, rather than create further division.

"I really think it's important to keep bringing people with you. And I don't just talk about it, that is actually how I have campaigned," she said in Charleston earlier this week. "But it is also how I have won my races. But it is also how I've governed."

With lower expectations for the three candidates on Saturday, part of their focus this week turned away from South Carolina and already towards Super Tuesday states, including the southeastern corner of the country: North Carolina, Virginia or Tennessee for Klobuchar and Buttigieg, and parts of the South for Warren, such as Arkansas and Texas.

For the party as a whole, Democrats will be anxious for signs of an engaged electorate in South Carolina, after lackluster turnout in Iowa, and slightly larger turnout in New Hampshire and Nevada that still fell short of 2008's record levels.

But in one early indication for state Democrats, early absentee voting in the Democratic primary surpassed 2016's numbers on Thursday, reaching 50% higher than at the same point four years ago, according to the Post and Courier.