More than 2,000 people, including Hollywood star Mark Ruffalo, are signing up for Democracy Spring, a coalition of 90 groups that's planning an April sit-in at the Capitol.
The group is demanding an end to big money in politics and wants reforms to better protect the right to vote and fair and free elections.
“I think this is a huge moment for our country,” Kai Newkirk, Democracy Spring's lead organizer, told reporters Thursday.
The organizers said their movement has broad support in the U.S. but they are frustrated Congress is doing nothing.
Democracy Spring is partnering up with Democracy Awakening, another coalition of over 150 organizations, to hold the non-violent sit-in at Capitol Hill on April 17.
The 2,000 activists who've signed up to participate say they are ready to risk arrest to make their case.
In addition to Ruffalo, Harvard Law Professor Larry Lessig, who briefly ran for the 2016 Democratic nomination, and Zephyr Teachout, a law professor who unsuccessfully challenged New York Gov. Andrew Cuomo in the 2014 Democratic primary, are also signing on.
Both Teachout and Lessig made campaign finance reform a centerpiece of their bids.
Supporters said the event will highlight solutions available to Congress now. The coalition is promoting four bills: the Government by the People Act & Fair Elections Now Act; the Voting Rights Advancement Act of 2015; Voter Empowerment Act of 2015; and the Democracy for All Amendment.
Their campaign will begin with an event on April 2 at the Liberty Bill in Philadelphia. Activists will then take part in a 10-day, 140-mile march to Washington, D.C., for a mass sit-in if Congress hasn't acted.
“This is going to build into what I believe can be an ‘Occupy Wall Street’ moment,” Newkirk said. “We can change the media narrative and force folks to pay attention.
"Whether Congress takes action or not, we are going to send a message that people cannot ignore,” he added.
This story was updated on Feb. 19 at 1:24 p.m.