Democratic Senate candidates see fundraising boom even as Biden campaign loses donors

As concern over President Joe Biden's fundraising prospects in the wake of his debate performance reaches a fever pitch, a number of Democratic senatorial candidates from hotly-contested races are reporting record hauls.

This week, at least six Senate candidates competing in highly targeted races are reporting that they've raked in millions of dollars in the second quarter of this year: Sen. Sherrod Brown of Ohio raised a whopping $12.8 million, Rep. Ruben Gallego of Arizona raised $10.4 million, Sen. Jacky Rosen of Nevada raised $7.6 million, Rep. Colin Allred of Texas raised $10.5 million and former Rep. Debbie Mucarsel-Powell of Florida raised $4.8 million. Rep. Elissa Slotkin of Michigan, the leading Democrat seeking her state's open Senate seat, brought in $6.45 million during the last fundraising quarter, her campaign said.

For some, like Rosen, Gallego and Slotkin, those yields are their largest thus far this cycle, according to their campaigns -- with a swath of the money coming from first-time donors.

The gains come as Democratic donors -- some high-profile -- have said they are ready to shift money from the Biden campaign to down ballot races amid a frenzy in Washington over the possibility of a second Trump term in the White House and fear that competitive congressional races could be negatively affected by Biden staying at the top of the ticket amid concern over his age and mental cognition.

"I talked to a bunch of big donors, and they're moving all their money to Congress and the Senate," Endeavor CEO and Democratic donor Ari Emanuel said at the Aspen Ideas Festival in Colorado in early July.

'"We are not going to win in November with this president. On top of that, we won't win the House, and we're going to lose the Senate," Hollywood icon and Democratic donor George Clooney wrote in his New York Times op-ed published on Wednesday, which called for Biden to drop out of the race.

Biden's politically devastating debate performance came just a few days before the U.S. Supreme Court delivered the presidential immunity ruling that benefited Donald Trump. Coupled together, a national Democrat with knowledge of Senate races told ABC News, the events have triggered a surge of support for Senate Democrats from both grassroots and major donors.

In the week following the debate and the ruling, multiple major donors sent new six-figure contributions to Democratic campaigns, they said, with one major donor increasing their support this week for the Democratic Senatorial Campaign Committee by 50%.

The DSCC has had its largest major donor fundraising month in June since 2008, the national Democrat said, with its digital and grassroots fundraising operation breaking multiple records in the days after the debate, marking its strongest online fundraising stretch this cycle.

A number of high-dollar donors are considering putting their donations to Biden on pause, as the "freakout" among donors continues to escalate. Some donors who have spoken with ABC News indicated that they were halting their financial support with uncertainty where it would go next– potentially to congressional races.

Senate Campaigns report seeing significant fundraising boosts post debate

One Senate campaign from a battleground state told ABC News that in the aftermath of the debate, a swell of major-dollar donors doubled down on their investments and small dollar donations overperformed projections by 150%.

Another Senate campaign, from a different battleground state, told ABC News that it saw a real increase in donors, both grassroots and high-dollar donors the 72 hours after the debate -- "some of our strongest fundraising days."

"It isn't surprising that there would be a surge of donations towards Democratic senators and Senate candidates, I think that is entirely because they know that the Senate is a stopgap against the court if Donald Trump becomes president again," said Justin Barasky, a Democratic strategist who formerly served as a senior adviser to the Democratic Senatorial Campaign Committee.

"Democratic donors are watching the Supreme Court repeatedly attack fundamental freedoms, and they know the only way to ensure the court doesn't push our country even further towards authoritarian rule is to elect as many Democratic senators as possible. The surge that has happened is not surprising, if donors are worried about the White House. It isn't surprising that they have sort of surged money towards Dem[ocratic] Senate candidates and Senators because … they can stop a hypothetical President Trump from appointing more bad justices," Barasky added.

For Gallego, who is likely to face Republican firebrand Kari Lake for retiring independent Sen. Kyrsten Sinema's seat in Arizona, 50% of his 119,000 donors were giving to his bid for the first time, according to his campaign.

For Rosen in Nevada, more than 33,000 donors to her campaign were first-time contributors, they said, and 96% of the donations were $100 or less. The incumbent is set to face off against Republican Sam Brown in November.

Last quarter's fundraising haul is the most that Slotkin has raised since she jumped into the race for Michigan's open Senate seat in February 2023, according to her campaign, with 56% of those donors new.

Slotkin said Wednesday that she's listening to constituents and voters in Michigan before "doing anything out of emotion" regarding taking a stance on Biden remaining the party's nominee.

"I'm going to do what's best for the things that I can control," Slotkin told The Detroit News. "In the end, the decision is Biden's -- only he can make this decision. All I can do is provide thoughts and input and understanding about where Michigan is, but it's over to him."

State of the Senate amid concern for Biden's candidacy

Unlike House Democrats, senators from the party have remained pretty mum on Biden's White House bid -- with Sen. Peter Welch of Massachusetts, becoming the first from the upper chamber to call for Biden to withdraw from the 2024 race in an op-ed on Wednesday.

But like Slotkin, some of the most vulnerable Democratic Senate candidates have attempted to distance themselves from Biden following the debate.

Sen. Jon Tester of Montana, who is one of two Democratic Senate candidates trying to hold onto seats in states where Trump won, said that Biden needs to "prove" to him that he's up for the job.

"President Biden has got to prove to the American people -- including me -- that he's up to the job for another four years. Meanwhile, I'll continue to do what I've always done: Stand up to President Biden when he's wrong and protect our Montana way of life," Tester said in a statement to ABC News.

Tester and Brown, the other red-state incumbent Democrat in the Senate, during a closed-door meeting among Senate Democrats Tuesday was among a group that conveyed concerns about Biden's ability to win in November.

Approached by ABC News Senior Congressional Correspondent Rachel Scott about that reporting, Brown was tight-lipped.

"I am hearing legitimate concerns from Ohio voters," Brown said when asked about his confidence in Biden. "My job is to listen to them, my job is to go to hearings like this to fight for lower drug prices to fight for Ohio workers."

Senate Democrats are largely out-performing Biden in most polls of battleground states. Though just this week, the Cook Political Report reported worsening ratings for Democrats in six close states, including Nevada and Arizona. Thus, Democratic Senate candidates will need a steady stream of fundraising in order to maintain control of the chamber.

On Thursday, Senate Democrats were holding a special caucus lunch to hear from senior Biden advisers Mike Donilon and Steve Richetti, and Biden Campaign Chair Jen O'Malley Dillon. The lunch will take place Thursday afternoon at the DSCC headquarters in Washington D.C, according to a source close to Senate Democratic leadership.

–ABC News' Allie Pecorin, Zohreen Shah, Selina Wang and Rachel Scott contributed to this report.