Biden's post-debate struggles could drag down Democrats in tough races. Here's how they're responding

President Joe Biden's debate performance has ignited fears among Democrats that a Biden-led ticket could threaten down-ballot candidates as Democrats seek to hold control of the Senate and win back a majority in the House of Representatives.

Democratic politicians and party operatives have expressed concerns that Biden could depress Democratic turnout in November, dragging down candidates lower on the ticket -- and noted that some donors have begun to shift their focus down-ballot to hedge against the prospect of a victory for former President Donald Trump.

To take control of the House in November, ensuring themselves a bulwark against a second Trump administration, Democrats need only to flip four seats. The president’s tailspin following the first debate could threaten that goal, several Democrats have said.

"There must be a serious reckoning with the down-ballot effect of whomever we nominate," Democratic Rep. Ritchie Torres of New York wrote in a statement Wednesday. "If we're going to choose a particular path, we should be clear-eyed about its consequences."

Those consequences could fall directly on Democrats such as Minnesota Rep. Angie Craig, up for reelection in the state's competitive 2nd District.

Last week, Craig became one of several elected Democrats who have publicly called for Biden to step aside.

"I do not believe that the President can effectively campaign and win against Donald Trump," she said in a statement.

Democrats such as Craig, who face difficult reelection contests, must weigh the political calculus of whether and how strongly to voice concerns about Biden.

After reports that Pennsylvania Rep. Susan Wild expressed worries in a private call with House members about running on the same ticket as Biden, Wild issued a statement acknowledging, in part, that she "expressed the same concerns that Americans across the country are grappling with, about President Biden's electability at the top of the ticket."

Meanwhile, some senators up for reelection in battleground states have withheld their own opinions about Biden -- at least publicly.

"I'm focused on my own reelection campaign, continuing my record as one of the most bipartisan and independent Senators, and putting politics aside to get things done for Nevada," Sen. Jacky Rosen said in a statement.

Wisconsin Sen. Tammy Baldwin told ABC News after a recent campaign event that she was "focused very much on getting the vote out for Democrats in Wisconsin."

Asked if she worried about Biden's effect on her race, Baldwin said, "I'm listening carefully to what my constituents and voters have to say in Wisconsin and certainly sharing those comments with the president's advisors."

Reps. Jared Golden of Maine and Marie Gluesenkamp Perez of Washington, meanwhile, have chosen a more controversial route by saying outright that they believed Biden would lose to Trump in November.

But adding to the drumbeat of anti-Biden rhetoric could backfire, party operatives say, turning supporters off just when Democrats need the reverse.

"​​It puts candidates in a weird position, it puts the party in a weird position, it obviously puts our nominee for president in a weird position," said Matthew Grodsky, a leading party strategist in Arizona. "It's much better to do this stuff behind the scenes and work out these types of differences, rather than posting every thought publicly."

Another prominent swing-state strategist told ABC News that they "think campaigns are a little nervous right now."

"But I think that the thing that would help them settle the most is to have it settled -- who's going to be at the top of the ticket," the strategist added.

It's not all bad news for down-ballot Democrats, though.

Since the debate, six Democratic Senate candidates in tough races have reported eye-popping fundraising hauls for the second quarter of this year, including three -- Sen. Sherrod Brown of Ohio, Rep. Ruben Gallego of Arizona, and Rep. Colin Allred of Texas -- who topped $10 million.

Biden's debate performance came just a few days before the U.S. Supreme Court delivered the presidential immunity ruling that benefited 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.

Two battleground-state campaigns confirmed to ABC News that they saw a surge in donations in the days following the debate.

Grodsky said he had seen a shift in donor focus to down-ballot races, according to his conversations with donors, candidates who have spoken with donors and colleagues across multiple states.

"I can confirm that's definitely a thing," he said, though he noted that "the president has raised an enormous amount of money, and it looks like he still is, so I don't think it's a five-alarm fire."

The other strategist, however, said they hadn't seen a donor shift down-ballot so far.

Lauren Harper, a cofounder of a group called Welcome PAC that supports Democrats running in red districts, told ABC News that she had also not yet sensed a change with donors focusing on down-ballot races.

But, Harper suggested, she won't be complaining if she does.

"If you are figuring you're going to lose in one place," she said, "I would think it's smart to pick it up in another place that you have more confidence in."