Joe Biden is moving closer to consolidating the support of moderate Democratic voters and donors after a resounding victory in South Carolina and the departure of Pete Buttigieg and Amy Klobuchar from the party’s presidential race.

The former vice president is set to get a massive bump from both exiting candidates: a source familiar with the plans told CNN that Buttigieg will endorse Biden on Monday in Dallas at the same time as Klobuchar.

The question heading into Super Tuesday is whether the former vice president and his growing momentum will be enough to keep pace in the delegate race with Vermont Sen. Bernie Sanders.

He’ll also need to stave off former New York Mayor Michael Bloomberg, whose ads have blanketed the airwaves and social media apps in Super Tuesday states. Bloomberg could be positioned to be a spoiler for Biden, helping Sanders rack up delegates by dividing moderate voters.

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Fourteen states and American Samoa will vote on Tuesday on the biggest day of the Democratic primary — with 34% of the party’s pledged delegates up for grabs. Sanders expects a big win in California, the day’s biggest prize, as well as in other western and northeastern states. Biden is aiming to build on his advantage with African American voters in southern states like Alabama and North Carolina. The biggest battleground could be Texas, where Biden is campaigning Monday, and Sanders is hoping to recreate the Latino-led coalition that led him to victory in Nevada.

Biden’s blowout win in South Carolina is rapidly reshaping the Democratic race, as Biden moves to lock down the party’s Democratic wing.

The first major domino fell Sunday night, when Buttigieg — the former of South Bend, Indiana and a moderate whose criticisms of Sanders were often similar to Biden’s — dropped out of the race.And then on Monday, Klobuchar, through a campaign aide, confirmed she would be exiting the race and endorsing Biden at an event in Dallas.

A source familiar with the matter said Buttigieg was unwilling to risk accumulating delegates for a campaign with no path to the nomination, fearing that doing so would help Sanders build an “insurmountable” lead.

After delivering his concession speech, Buttigieg spoke to Biden by phone, two people familiar with the conversation say.

Biden congratulated Buttigieg on his campaign and asked for his endorsement. Buttigieg did not make an immediate decision, telling advisers after the call that he wanted to think about it overnight. An endorsement for Biden is likely, two people close to Buttigieg say, but whether he makes the decision before Super Tuesday is unclear.

Virginia Rep. Don Beyer, who had endorsed Buttigieg, switched his support to Biden on Sunday night — the latest Virginia Democrat to endorse the former vice president before Tuesday, when the state will be a closely watched battleground. Virginia Rep. Jennifer Wexton, part of the 2018 wave that helped Democrats take control of the House, also endorsed Biden on Sunday.

Biden’s allies, meanwhile, intensified attacks on Bloomberg, whose late entrance to the race in November was motivated by the view that Biden was weak and Sanders was on course to become the nominee.

In a memo to supporters Sunday night, three strategists with the pro-Biden super PAC Unite the Country wrote that Bloomberg “should decide soon if he wants to be the reason why Bernie Sanders is the nominee of the party.”

Still, Biden’s campaign faces massive financial and organizational disadvantages compared to Sanders, Bloomberg and Massachusetts Sen. Elizabeth Warren, who has had aides organizing in Super Tuesday states for months.

Biden’s campaign said he raised $10 million on Saturday and Sunday alone — more than he’d raised in the entire month of January.

But Biden was outraised in February. Biden said Sunday he raised $18 million in February — well off the $46 million that Sanders raised and the $29 million hauled in by Warren. Bloomberg, meanwhile, has spent $170 million on Super Tuesday ads — compared to Biden’s $2.2 million Super Tuesday advertising plan.

Someone who is not expected to intervene to help Biden: Former President Barack Obama. The two spoke by phone Saturday night after Biden’s win in South Carolina. But a source close to the former president said Obama’s plans to stay out of the Democratic primary haven’t changed.

“We are skeptical that an endorsement coming from us could truly change the political winds right now,” the person close to Obama told CNN. If Obama were to endorse Biden, the person said, there is “a very real chance it backfires.”

Obama also spoke with Buttigieg by phone late Sunday night, praising his campaign and his decision to leave the race, two people familiar with the conversation said. Obama noted how difficult it is to disappoint supporters and admirers. Obama told Buttigieg he ran a historic campaign to be proud of.

The former president made clear the decision on whether to endorse a candidate is Buttigieg’s alone to make, two people familiar with the call say. The two discussed the leverage that Buttigieg has now — and how he could be most helpful in shaping the race.

Before a quick conversation with reporters on Sunday night, Sanders congratulated Buttigieg on what he described as a trailblazing, “brilliant campaign.”

Asked if he believed that his moderate rivals were privately discussing ways consolidate their support, and derail his bid, Sanders didn’t reject the premise.

“I think it’s no secret that the establishment is getting very nervous,” he said. “Whether it is the corporate wing of the Democratic Party or the political leadership.”

Biden’s Super Tuesday strategy

Biden’s campaign expects Sanders to emerge from Tuesday’s contest with a lead in delegates, two Biden campaign aides said. Its goal is to “remain competitive” with Sanders, the aides said — and to put enough distance between Sanders and Biden and everyone else in the race that it’s clear it has become a two-person contest.

The Biden campaign’s approach to Super Tuesday starts with congressional districts in the South where a majority — or at least large share — of voters are African American.

A Biden aide said the former vice president can win Tuesday in states with demographics similar to South Carolina — including Alabama, Arkansas, North Carolina and Tennessee.

Biden has also said he believes he can win Texas. He was campaigning Monday in Houston and Dallas.

Key targets cited by aides include Alabama’s 7th District, which includes Selma and parts of Birmingham and where Biden was endorsed by Rep. Terri Sewell, and North Carolina’s 1st District, where Rep. G.K. Butterfield is another prominent backer of the former vice president.

Biden’s aides believe other candidates could fall below the 15% support necessary to earn delegates in those districts, making wins there for Biden even more valuable in the drawn-out delegate battle that now looks increasingly likely.

“People died for the right to vote — in my district, especially. And we’re not going to be held hostage to someone who just can spread money,” Sewell said of Bloomberg. “I think that this kind of support is earned, and Joe Biden’s earned it.”

Buttigieg’s exit helps Biden lock down moderates

Buttigieg did not endorse a candidate when he ended his presidential campaign on Sunday, instead using the moment to thank his former competitors for “demonstrating what public service can be.”

But the end of Buttigieg’s run — and the fact that he is getting out the day after Biden romped in South Carolina — signaled where the former mayor is leaning.

Buttigieg spent the final weeks of his campaign lambasting Sanders by labeling his movement an “inflexible, ideological revolution” and suggesting that his nomination would be a death knell for House and Senate Democrats in tough races.

Speaking in South Bend on Sunday, Buttigieg issued a similar warning to the one he made after Sanders swept the Nevada caucuses. He didn’t name the Vermont senator this time, but again suggested Sanders would be a drag on down-ballot Democratic candidates.

“We need a broad-based agenda that can truly deliver for the American people, not one that gets lost in ideology,” Buttigieg said. “We need an approach strong enough not only to win the White House but to hold the House (of Representatives), win the Senate and send Mitch McConnell into retirement.”

While Buttigieg did attack Biden during his campaign — he suggested days before Iowa that Biden was selling from the “same Washington playbook” and recycling “the same arguments” — the two were far more ideologically in line than others.

And Biden, at one point, told an audience in New Hampshire that he’d consider “Indiana” — a shorthand reference to Buttigieg — among the 2020 candidates who’d be an ideological fit as a possible vice presidential nominee.

Biden and Buttigieg, according to aides, exchanged phone calls on Sunday ahead of the former mayor’s decision to get out. A separate source familiar with the matter told CNN that there has been staff-level communication between their campaigns on Sunday.

And some Buttigieg donors informed top Biden supporters after the South Carolina results came out that they were eager to support the former vice president when the former mayor exited the race.

Could Buttigieg’s exit also help Warren?

Buttigieg’s supporters, though, are far from monolithic. Conversations with hundreds over the course of the campaign revealed a mix of second choices, including Biden and Warren. And while rare, some Buttigieg supporters did tell CNN that they were considering Sanders, too.

On Sunday, Buttigieg did not reprise any of the attacks he leveled during the campaign at Warren, the primary’s other leading progressive. Both Buttigieg and Warren have performed well with college-educated white voters, entrance and exit polls have shown.

Despite their differences on policy, and a fiery December clash over donors and transparency, Buttigieg and Warren appeared to draw from a similar cohort of voters. According to a recent Quinnipiac poll, Buttigieg’s supporters, when asked who their second choice would be, were split between Warren and Klobuchar, with 26% eyeing each — a number touted in a tweet by Adam Green, co-founder of the Progressive Change Campaign Committee, and one of Warren’s staunchest advocates.

The overlap between Buttigieg and Warren, especially among white, college-educated Democrats, became evident late last year. But after Buttigieg’s strong showing in Iowa, it appeared that the former South Bend, Indiana, mayor had won them over. Now, similarly-inclined voters in the Super Tuesday states and beyond will be looking for a new home.

Shortly after the news broke, the Working Families Party, which endorsed Warren last year, sent out a split fundraising email — subject line “Pete Buttigieg (!)” — shortly before Buttigieg spoke in South Bend.

“Elizabeth Warren is currently in second place in multiple national and state polls, including in the delegate-rich state of California,” it said. “The polls also show her as the second choice for a LOT of Pete Buttigieg supporters.”

The Warren campaign was mostly mum on Sunday night. Warren in a tweet thanked Buttigieg, adding, “I know you’ll continue giving back and serving our country for many years to come.”

His departure from the race might well serve her campaign in the much nearer term.