The House Democratic majority is fragile.

The National Republican Congressional Committee recently released its list of 55 targeted districts — many of which are districts Democrats flipped from red to blue in 2018. Republicans are sure to spend a lot of money trying to win them back.

The coming 2020 election will be a huge test for these new House Democrats, but it will also be a test for one of the key messages that helped them win — dozens of incoming new members pledged never to take money from corporate PACs.

Already, a few are getting pressure from longer-tenured House Democrats to ditch their pledge ahead of 2020. Three first-term members told Vox they’ve been approached by longtime members who suggested they should consider walking back their no-corporate-PAC pledge to gain a financial edge.

“Mostly from members who have been here a long time ... a few of whom have been very dismissive and said, ‘You’re going to have to get rid of that,’” Rep. Susan Wild (D-PA) told Vox. Wild, who won a special election to replace longtime Republican Rep. Charlie Dent, added that she doesn’t plan to go back on her word.

She isn’t alone. The seven first-term Democrats Vox talked to for this piece made it clear they plan to stick to their promise and aren’t planning to take corporate PAC money when they run in 2020.

Even as House Democrats passed a sweeping anti-corruption and pro-democracy reform bill known as HR 1 last week, the prodding Wild and other freshmen have been getting from some longtime members is indicative of a larger debate going on in the Democratic Party about money in politics. Some think Democrats should be realistic — if money gives them a competitive advantage against President Donald Trump and Republicans, they should take it.

Others believe Democrats should pay attention to the energy stirred by Bernie Sanders, who made the 2016 presidential election surprisingly competitive by railing about the political influence millionaires and billionaires can buy. Polling shows that getting money out of politics is an incredibly popular issue that resonates with a majority of independent voters.

“I think this no corporate PAC thing really came out of the 2018 energy, and I think it’s partly a result of so many first-time candidates — so many of us who were told, ‘You can’t win these seats,’” said Rep. Katie Porter (D-CA), an Elizabeth Warren protégé who became the first Democrat ever to win her conservative Orange County district.

How much of a difference will corporate PAC money make in 2020?

Many Democrats who won conservative districts spent most of the 2018 cycle being told they could not win their races, and certainly not without taking corporate PAC money.

“When I started getting in touch with people in politics, I [heard] a lot of skepticism about not taking corporate PAC money, but I also got a lot of skepticism about my race as a whole,” said Rep. Andy Kim (D-NJ), who beat a formidable Republican incumbent, Tom MacArthur.

Wild remembered that a former campaign manager “wasn’t thrilled” with her decision.

“It’s something I think about every day in context of a reelection in 2020,” Wild said. “It was a little easier last year, because there was just so much energy and enthusiasm about Democratic candidates, and Democratic women in particular, that the money came in. We’re going to have to work on creative fundraising.” Wild still takes money from organized labor and PACs of advocacy groups like Planned Parenthood and NARAL, but she’s also looking at how she can boost her online fundraising presence.

As Wild demonstrates, there’s an important distinction to make here: Just because these Democrats aren’t taking corporate PAC money doesn’t mean they’re saying no to all PAC money. Many accept donations from advocacy group PACs like Planned Parenthood Action Fund and House leadership PACs like House Majority Leader Steny Hoyer’s AmeriPAC. There’s plenty of reason to question that saying no to corporate PACs actually erodes a financial advantage; Democrats far out-fundraised Republicans in 2018.

As OpenSecrets’ Karl Evers-Hillstrom reported, PAC spending on congressional candidates was dwarfed by individual donor spending: $494 million in PAC money compared to $1.7 billion from individuals who donated to candidates by October 2018. And these candidates were still getting money from House leadership PACs, many of whom take money from corporate sources:

Among those groups are Leadership PACs, from which the winning no-corporate PAC Democrats took a total of nearly $2.95 million this cycle. The PACs, run by members looking to raise money for their fellow party candidates in order to gain leadership positions, are funded almost entirely by corporate and trade association PACs.

Other new members are fretting about the amount of time lost to fundraising for their reelection campaigns that they could spend doing the legislative parts of their job.

“Unfortunately, yes, fundraising never stops,” Rep. Tom Malinowski (D-NJ) told Vox. “The political fundraising demands really do make it hard to devote sufficient time to the business we were sent here to do. And that’s a daily struggle to me and almost everybody I know.”

For this reason, Malinowski is a huge fan of the public campaign finance program HR 1 would set up (he’ll have to wait a while, as the bill has no chance of passing the Republican-controlled Senate).

These first-term Democrats are under no impression they’ll actually be able to get HR 1 off the ground before 2020, but after hearing voters complain about money in politics last cycle, they’ll be able to go back to their districts and say they kept their promise.

“It’s easier as a first-time candidate on the campaign trail to say things in Washington are broken,” said Rep. Abigail Spanberger (D-VA). “You can only say that once.”

How no-corporate-PAC freshmen are changing Washington’s culture

Even before HR 1 was passed, some first-term members told Vox their mere presence in Washington was changing the status quo, especially where lobbying was concerned. Rising star Alexandria Ocasio-Cortez has gotten attention simply for sitting through long committee hearings many of her peers can’t attend because they are too busy fundraising.

Before they were even sworn in, other Democrats were being hounded about whether they would keep pledges they made on the campaign trail. The biggest one was whether moderate first-term Democrats would keep their promise not to vote for House Speaker Nancy Pelosi (several did keep that pledge). Another was whether they would keep rejecting corporate PAC money.

“That’s another pledge where people have asked me if I intend to keep it, which is pretty illustrative, I think, of the culture here,” Rep. Jason Crow (D-CO) told Vox, sitting outside freshman orientation in December. “That people think they’ll take a pledge on the campaign side and then change it after they get elected.”

House Democrats passed HR 1 late last week, a sweeping bill to get money out of politics by increasing transparency around donors and cracking down on lobbyist influence on Capitol Hill. The bill would also expand voting rights for Americans by implementing provisions like automatic voter registration.

“It’s a shock to the culture here to actually try to follow up on something you ran on,” said Rep. Max Rose (D-NY), a first-term member from Staten Island and a vehement supporter of HR 1. “But what we are seeking to do is not just to change and eliminate some of the perverse incentives that have riddled this system, but also to change the culture here in Washington, DC.”

As Pelosi said on the steps of the Capitol before the vote, HR 1 was an effort spearheaded by the House’s newest class.

“When our freshmen took the oath, they made a difference, ensuring the priorities of their communities would be the priorities of the Congress,” she said.

It’s not as if these first-term members are forswearing all meetings with corporate lobbyists, but the meetings come without the added pressure of doing favors for some campaign cash.

“I have no problem talking to corporations. I’m a capitalist, and corporations employ people in my district and should have a voice at the table,” said Malinowski. “I just want that voice to be disconnected from campaign contributions. It allows me to meet with lobbyists and just talk about substantive policy without that little voice in the back of your head saying, ‘You might need this person to help you get reelected.’”