A new campaign-finance-reform PAC with ambitious spending goals is adding six battleground House districts to its target list.

End Citizens United PAC is endorsing Democrats Michael Eggman in California, Josh Gottheimer in New Jersey, Morgan Carroll in Colorado, Monica Vernon in Iowa, Brad Schneider in Illinois, and Pete Gallego in Texas. Each challenger is running against a Republican House member.

To date, End Citizens United PAC has donated about $250,000 to Democratic candidates out of the roughly $3.8 million it has raised—thanks to the use of the voluminous email list developed by Ready for Hillary. The organization’s aim is to elect Democrats who favor overturning Citizens United and other Supreme Court decisions that have fueled more money in politics.

Schneider and Gallego, two former Democratic congressmen who lost narrowly in 2014, saw among the highest levels of reported outside spending in House races last year. Outside groups poured about $10.4 million into Schneider’s race and roughly $5.4 million into Gallego’s seat, according to data from the Center for Responsive Politics. Schneider's race was one of only a handful in history to feature eight-figures worth of outside spending.

“The former members we’re endorsing have a strong record of wanting to get the untraceable money out of politics,” said Richard Carbo, the PAC's communications director. “They know directly what this means.” (One senior adviser for the PAC, Valerie Martin, is a senior adviser for Schneider’s campaign, while another senior adviser, Reed Adamson, was once Schneider’s chief of staff.)

From January through June, End Citizens United PAC raised about $1.5 million, a sum that’s similar to what other traditionally big-spending groups have collected this cycle. Over the same period, Senate Majority PAC, for example, drew $1.3 million, while House Majority PAC netted $2.1 million.

Through an independent-expenditure arm set for a launch in spring, the group is planning to spend an additional $25 to $30 million to boost candidates in 2016. That would put it among the biggest spenders in congressional politics.

For now, End Citizens United PAC is cutting checks from $1,000 to $10,000, depending on a candidate’s level of need. The group has given $9,500 to each of the seven Senate contenders it’s endorsed, investments that Carbo argued will help them beat back early attacks.

One of the candidates, Russ Feingold in Wisconsin, has already had $1.2 million spent against him—though Democratic-aligned outside groups have spent even more in his favor. Six years ago, Feingold disavowed outside spending, but the former senator has said that doesn't make sense in today's campaign finance environment.

Carbo said End Citizens United has not finalized estimates of how much the group spent to raise its $3.8 million haul.

End Citizen United PAC’s newest slate of endorsements also features 13 House incumbents, including Reps. Jim Costa in California, Brad Ashford in Nebraska, and John Delaney in Maryland. The organization has now backed 35 House and Senate Democratic candidates.

On top of the donations, End Citizens United PAC is conducting polling in key battleground races. The group recently released surveys showing Michael Bennet in Colorado and Tammy Duckworth in Illinois leading close Senate races, while Feingold enjoyed a larger lead in Wisconsin.

Armed with Ready for Hillary’s email list, the group’s supporters have raised an additional $20,000 directly for Feingold and nearly $15,000 for Bennet.

But despite End Citizen United PAC’s early financial success, the organization still faces a steep climb in pushing its pet issue.

In 2014, a super PAC created by Harvard professor Lawrence Lessig launched with a similar goal, only to achieve little after spending $10 million. End Citizens United PAC has argued that its tactics differ from that group, noting that its efforts are debuting much earlier in the cycle.

“This is an issue people are passionate about,” Carbo said. “More than anything, they are tired of this influence of dark money in politics.”

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