The House Judiciary Committee was in the middle of considering a resolution expanding Democrats’ impeachment proceedings when Rep. Matt Gaetz decided to get personal.

Decrying Judiciary Committee Chairman Jerry Nadler’s escalating impeachment inquiry into President Trump, the right-wing Florida congressman fired a shot at the integrity of the hearing—and at the man holding the gavel.

“I would hope,” Gaetz said, “that these proceedings are not about the chairman’s upcoming primary challenge.”

The quip prompted some shocked groans on the Democratic side of the dais—and silence from Nadler. But the cheap shot raised by Gaetz is central to the argument that one of Nadler’s Democratic primary opponents, Lindsey Boylan, eagerly makes herself.

“Without my challenge, I have no doubt in my mind he wouldn't be aggressively acting the way he is,” said Boylan in a recent interview. “But it's not enough.”

Boylan, a former official in the administration of New York Gov. Andrew Cuomo, is one of four candidates seeking to unseat Nadler in the New York City district he has represented since 1992. She has raised some $350,000 for her campaign so far—$85,000 of it from herself—and is the best-resourced candidate in a field of challengers that includes two other women who are also several decades younger than Nadler and are also enthusiastic backers of lefty policies like the Green New Deal.

It’s not just Nadler who is feeling some fresh heat from his own party. After years of targeting moderates and backbenchers, anti-establishment elements in the Democratic Party are directing their energy toward unseating their most influential lawmakers, smelling blood after Rep. Alexandria Ocasio-Cortez of New York shocked the political establishment by defeating former Rep. Joe Crowley in a 2018 primary.

That trend is cresting in 2020, with upstarts around the country taking on the Democratic lawmakers who are setting the party’s priorities on not only impeachment and oversight but also health-care and spending policy. Serious challengers with electoral experience and promising grassroots support are gunning for no fewer than five influential committee chairs—Nadler, Richard Neal of the Ways and Means Committee, Eliot Engel of the Foreign Affairs Committee, Nita Lowey of the Appropriations Committee, and Frank Pallone of the Energy and Commerce Committee. The top two House Democrats, Nancy Pelosi and Steny Hoyer, also face primary rivals who have garnered some attention, but defeating those two is a far taller task.

Several of these primaries will air substantial policy differences over the issues dominating debate among Democrats right now, like Medicare-for-All. In other races, the ideological daylight between candidates will be slim.

But on the whole, 2020’s bumper crop of challenges centers on how well a new generation of Democrats can sell the idea that the party’s old guard is no longer capable of forcefully leading on a range of key issues—including, as Gaetz’s trollish interlude underscored, their commitment to holding Trump’s feet to the fire.

According to Neal Kwatra, a Democratic strategist in New York, the phenomenon amounts to an escalation in Democrats’ internal debates over what they stand for. “What you’re seeing is, these broader challenges are much less about ideology and more about the fighting spirit of the party, what it’s willing to do, how it’s going to hold Trump and the Republican Party writ large accountable,” Kwatra told The Daily Beast. “I think that’s a generational challenge.”

The challengers to Neal and Nadler in particular reflect the phenomenon. Both chairmen face their most serious races in years from candidates loudly criticizing their commitments on everything from countering Trump to serving their districts.

That dynamic figures to put additional pressure on both chairmen as they try to steer their committees’ respective agendas, both of which are crucial to Democrats’ oversight of the president and policy priorities more broadly.

Neal, who has represented a solidly Democratic, largely white western Massachusetts district since 1988, is a moderate in today’s party. Due to his perch on the powerful Ways and Means Committee, he’s turned into something of a villain for progressives over his opposition to Medicare-for-All and his seemingly cozy relationships with corporate interests.

But it was Neal’s unique authority in the House to obtain Trump’s tax returns that was the final straw for some on the left. It was expected that Neal would leverage that power and ask for the tax filings immediately after Democrats took the House majority—instead, he did not do so until April, and he did not file a lawsuit to get them until July. A federal judge has blocked House Democrats’ bid to expedite that lawsuit; it could be months or years before it is resolved.

Alex Morse, the 30-year old mayor of the town of Holyoke, is weaving all these threads together in his challenge to Neal, which has already attracted some buzz in the media and among the left. “There’s an urgency to this moment and the urgency is not matched by this member of Congress,” Morse told The Daily Beast in an interview.

“His core argument, the argument of his supporters is, why would we give up that power—but what’s the point of having power if you’re not using it to hold this president accountable?”

The essence of that critique is the same in Nadler’s Manhattan- and Brooklyn-based district, but the Judiciary Chairman is a far different animal: among the most progressive senior leaders in the House, he has long enjoyed widespread support in this district, a hub of affluent liberals; one Democratic operative called him “the godfather of progressive politics in New York.”

Nadler’s challengers argue that the district deserves even more aggressive and more progressive leadership from its representative, not only on impeaching Trump but on climate change and income inequality.

Boylan in particular has relentlessly hammered Nadler for his handling of the impeachment inquiry, which she mocks as an “Inception-like, dream-within-a-dream” amid muddled messaging and widespread clamoring from the party base for Nadler and Pelosi to move forward in bringing an impeachment inquiry.

She casts the stalled impeachment proceedings as exhibit A of why the district should replace their representative. “This community has not seen Congressman Nadler lead on the issues of the day, and the one most in front of our faces, impeachment,” she said. “It's time for the next generation.”

In suburban New York City, meanwhile, the challenge to Engel, the Foreign Affairs Committee chair, leans less on his stewardship of oversight matters and more on generational change. His leading opponent, Jamaal Bowman, is a 40-year old school principal in the Bronx, and his campaign launch video pulled clips from Engel’s three decades in Congress to spotlight his political stances, like his advocacy for the 1994 crime bill, that have aged poorly.

The possibility of an energetic campaign from a black leader in the community excites many progressives, and Bowman is viewed as perhaps the most viable primary to a top Democratic lawmaker anywhere in the country. The fundamentals of the district also favor him more than other challengers: just north of Ocasio-Cortez’s district, it is deeply liberal and is one of only a few majority-minority districts to have a white representative.

These races are in their early stages, but the challengers have showed signs of fundraising prowess—or at least a willingness to self-fund enough to get their message out. New York Democrats are anticipating Boylan’s next fundraising quarter with interest to see if she can build on the $350,000 she’s raised so far. Another candidate running against Nadler, entrepreneur Holly Lynch, has seeded $125,000 of her own money to her campaign, which she is kicking off this week.

Nadler, who has often run unopposed for the Democratic nomination in New York’s 10th District, has faced well-resourced primary rivals before. In 2016, the last time there was a primary race, businessman Oliver Rosenberg poured $350,000 of his own money into a campaign that targeted Nadler almost entirely over his support for the Iran nuclear deal. Ultimately, Nadler won with nearly 90 percent of the vote.

Morse, meanwhile, called The Daily Beast from New York City, where he was tapping his network of friends and contacts for fundraising. He’ll need every cent he can get: Neal, who runs a committee that’s coveted by lawmakers as a veritable ATM for campaign cash, is already sitting on a campaign war chest of nearly $4 million.

But a hot primary is hardly a symmetrical war, say some operatives. “The beauty of it is,” said Karthik Ganapathy, who co-founded a progressive strategy firm intended to help challengers, “you don’t need to match incumbents one for one—you just need to have enough money to get your own message out there.”

Promising candidates could eventually earn the imprimatur of Justice Democrats, the left-wing organization that’s become a primary race kingmaker after sparking the rise of Ocasio-Cortez in 2018. The group has already endorsed several challengers, including Bowman.

Progressives might be clamoring for that leftward intervention to unseat some incumbents. But the idea of putting real time and resources into defeating loyal liberals like Nadler makes Democrats of different ideological stripes uneasy about the growing primary trend and concerned about the impact it could have on their stated top priorities—defeating Trump and taking back the Senate.

“How anyone views getting rid of Jerry Nadler as being anything on a top 2,000-list of problems the Democratic Party has,” said a veteran Democratic strategist, “is a ridiculous waste of time.”

A New York-based Democratic strategist told The Daily Beast that many progressives agree, and are not prioritizing Nadler’s race, instead focusing on Engel and Lowey.

“You should have to defend and show your record to the people. The fact that Nadler has to go to his community and say, here’s what I’ve done for you,” the strategist said, ”I think he can do that successfully.”

In an environment where all incumbents are watching their backs, it’s unlikely any will be caught as flat-footed as Crowley was in 2018. Notably, Neal is already coming out swinging against his opponent: in a statement to The Daily Beast, campaign spokesperson Peter Panos argued Neal was on the “front lines” of holding Trump accountable, and went after Morse’s stewardship of public schools in Holyoke, which were taken over by the state for poor performance in 2015, four years into his tenure as mayor. “Where was his urgency,” asked Panos, “to improve the schools in his city?”

Nadler’s campaign did not comment for this story. But New York Democrats say that the chairman’s extensive political network is poised to be put to work in his race. Key local leaders like Corey Johnson, the speaker of the New York City Council, are vouching for Nadler’s work in Congress and back home.“If there are members of the Democratic caucus who are out of sync with Democratic values, we should be challenging them,” Johnson told The Daily Beast, specifically mentioning Rep. Henry Cuellar, a Texas moderate who’s previously been backed by the National Rifle Association.

“We need to be strategic about these things,” he said. “Jerry’s not a person who’s out of sync with our values or hasn’t delivered for our district.”

Though even those who are bullish on the challengers expect most of them, if not all, to lose, there is hope that they might push these entrenched incumbents toward the positions the challengers are advocating. The New York Democratic strategist, for example, was quick to point to the campaign of Cynthia Nixon, who fell far short of upsetting Gov. Cuomo in the state’s 2018 primary but successfully pressured him to adopt more progressive positions.

“New York has entrenched representatives who aren’t shaking things up,” the strategist said. “These people just respond to primaries.”

The candidates themselves, of course, don’t view that as a consolation prize. “Success for me isn’t moving him anywhere,” Morse said of Neal, who he described as set in his ways. “It’s winning… These victories are more possible than ever.”

The small group of House Democrats who have defeated incumbents themselves are watching from Capitol Hill, meanwhile, with an attitude that this competition is good for Democrats, no matter how intense it may get.

"Look, it’s healthy,” said Rep. Ro Khanna, who unseated longtime Rep. Mike Honda in a deep blue Bay Area district in 2016. “We're living in a time of great anxiety, great change, and there should be competition for these seats. They aren’t entitlements.”

Neither, apparently, are fancy titles and powerful gavels. “Don’t try,” he cracked, “to become a committee chair in Congress.”