The Democratic National Committee’s stricter new requirements for presidential contenders to appear in party debates this fall triggered swift backlash Wednesday from Democratic candidates, many of whom are now in danger of being cut from the showcase events in September and October.

Some campaigns have already been struggling to reach the 65,000-donor threshold — or secure one percent in three qualified polls — to gain access to the first debates in June and July. But the DNC’s new criteria for the next round of debates — support from 130,000 unique donors as well as at least 2 percent support in four polls — is set to winnow out senators, governors and a number of other Democratic candidates who are not on a trajectory to hit the polling requirement and could have particular trouble hitting the donor requirement absent a viral moment or another future campaign-shaking event.

“The DNC is playing a gatekeeping function and they’re creating a filter to determine which candidates can make their arguments to the American people,” former Rep. John Delaney, who is largely self-funding his presidential campaign, said in an interview with POLITICO after sending a letter to the DNC to request more information on how the requirements were set. “A lot of very consequential rules are being created by the DNC, and we don’t know what goes into them.”

The rules are also reshuffling spending priorities among less-prominent candidates, some of whom have shifted plans to hire organizers based in Iowa or New Hampshire in order to pour money into donation-generating digital advertising.

Ads about making the debate stage have comprised the biggest slice of Democratic presidential advertising on Facebook, according to data from Bully Pulpit Interactive, a Democratic digital firm.

“Whether it’s hiring organizers, staffing, polling, any normal things that you do to build an operation — all has to get readjusted and cut because you now have to run Facebook ads,” said one Democratic presidential aide, granted anonymity to discuss the issue candidly. “You’re not building a movement that way.

“They are decimating the field,” the aide continued.

Another concern among Democratic strategists is that the donation criteria are forcing candidates "to blow up inboxes" with a high volume of fundraising emails to have a shot at the debate stage, potentially alienating the small-dollar donors who have become so valuable to Democratic campaigns up and down the ballot, said Jason Bresler, a Democratic consultant and the former political director of the Democratic Congressional Campaign Committee.

But the newer thresholds highlights the difficulty the parties — and the candidates — have with a field of two dozen candidates, some of whom are building national campaigns and some of whom appear more focused on using the presidential race as a platform. DNC Chairman Tom Perez has also long intimated that requirements to qualify for later debates would get steeper.

“For the debates to be meaningful, they have to winnow down the participants,” said Patti Solis Doyle, who managed Hillary Clinton’s 2008 presidential campaign. “This is the uncomfortable reality both the DNC and the candidates have to face.”

DNC communications director Xochitl Hinojosa defended the DNC’s debate qualifications as “fair, transparent and appropriate for each phase of the primary season,” she said in a statement. “We are confident that the two sets of criteria we have announced thus far achieve those goals, and have been communicated to candidates months before each debate."

Some campaigns have been concerned for weeks that the donor criteria for future DNC debates could shoot upward, and 2020 candidates on the bubble have spoken out more forcefully in recent weeks.

“I don’t think they should be winnowing the field,” Sen. Michael Bennet, who only jumped into the presidential race this month, told reporters in New Hampshire on Wednesday. “I certainly don’t think the DNC should be favoring national fundraising and cable television over the early states like New Hampshire.”

Sen. Kirsten Gillibrand has echoed that criticism, arguing that the criteria aren’t a measure of success, electability or candidate quality. Gillibrand, who was one of the premier online fundraisers in the Democratic Party in 2017 and 2018, is still striving to hit the 65,000-donor criteria for the first debates, though she has qualified via polling. (Gillibrand amassed more than 65,000 unique online donors in just the first quarter of 2017 for her Senate bid, as she voted against a string of Cabinet nominees during the early days of the Donald Trump administration, according to a POLITICO analysis of FEC data.)

And some candidates and Democratic operatives said that the DNC’s latest criteria could disproportionately affect candidates of color and female candidates.

“It doesn’t take a rocket scientist to look at that criteria and know who’s going to get kicked out,” said Jess Morales Rocketto, a Democratic strategist who worked on Hillary Clinton’s 2016 presidential run. “It’s easy to see that the debates in the fall are going to be a bunch of white men and, if that’s the case, that’s a big misstep.”

Four candidates have already publicly said they have crossed the new, higher donor threshold: Buttigieg, Harris, Sanders and Warren. O’Rourke and Biden each got roughly 100,000 individual donors on their campaign launch days, meaning they could have passed the 130,000 threshold by now.

Seven others have publicly said they’ve hit the halfway mark to 130,000: Booker, Castro, Gabbard, Inslee, Klobuchar, Williamson and Yang. (Yang tweeted he needed another “20,000 or so” donors to hit the new threshold on Wednesday, calling it “very doable.”) Among the candidates scrambling to catch up: Montana Gov. Steve Bullock, the only candidate running who has carried a Trump state.

In early polling, just eight candidates have crossed the modest 2 percent threshold in four qualifying polls: Biden, Sanders, Warren, Harris, Klobuchar, Booker, Buttiigeg and O’Rourke. None of these early polls will count toward qualifying for the later debates; only polls publicly released after the first debate in June will count in the criteria for the fall debates.

But the donation number has defenders, who argue that being able to amass a strong base of donors is an important way a campaign can prove viability, both in the primary and ahead of the general election.

“I think the number of grassroots donors you can bring in can be a leading indicator for how a candidate can connect” with voters, said Dan Kalik, a senior political advisor to MoveOn.org.

Other activist groups — including some who do not always see eye-to-eye with the DNC — voiced their approval for the increased grassroots threshold.

“Especially given what happened in 2016, the DNC is right to be concerned about any action they take to prematurely winnow the field,” Democracy for America communications director Neil Sroka said. “That said, the fact they’re not just relying on polling … and centering and welcoming into the fight people with a lot of grassroots support … struck us about as good as you can expect in terms of a requirement,” saying a fall debate stage packed with candidates with no viable path to the nomination could ultimately be detrimental to voters.

Yet these changes to the DNC’s primary rules sets thresholds for candidates long before votes are cast in Iowa and New Hampshire — once considered the official start to the nominating process. It’s “fundamentally transformed” the way presidential campaigns are run, said another presidential staffer, granted anonymity to discuss the issue.

“It seems like an artificially early time to cut off insurgent campaigns,” the staffer said.