Supporters of Vermont Sen. Bernie Sanders turned out to elect a slate of delegates who could be poised to take over the largest Democratic Party organization outside of Washington, D.C. Now the Sanders supporters claimed to have elected more than 650 delegates out of 1,120 available seats chosen at this month’s caucuses.

Those delegates will choose the next state Democratic Party chairman, along with other party officials and sound poised to change the very nature of the Democratic Party.

“One of the issues we’re looking to do is transform the party,” said Shannon Jackson, executive director of Our Revolution, the organization that grew out of the Sanders’s presidential campaign. “This is the first step in that process.”

Jackson spoke to The Hill about their Our Revolution get-out-the-vote effort to make sure supporters attended caucuses in each of the state’s 80 assembly districts. The group sent out more than 100,000 emails and delivered 40,000 text messages.

“There’s a lot of energy in the party right now. We need to move really quickly to harness this energy,” state Assembly Speaker Anthony Rendon (D) said in an interview, marveling at the turnout in his Los Angeles-area district.

California’s legislature has been at the vanguard of some of the most liberal policy programs in the nation, on everything from climate change to immigrant rights.

Sanders supporters hope to leverage their newfound power to convince Democratic majorities in the state Assembly and state Senate to embrace even more aggressive progressive positions.

“This is to basically force the issues that we vote on onto the legislators for action. So it’s a very serious sea change,” said RoseAnn DeMoro, who heads National Nurses United and the California Nurses Association, groups that backed Sanders during his 2016 presidential primary.

In May, California Democrats choose a replacement for outgoing state party Chairman John Burton. The nurses union backs Kimberly Ellis, a San Francisco-area party activist who runs Emerge California, a group that trains Democratic women to run for office.

Ellis will face Eric Bauman, who heads the Los Angeles Democratic Party and who backed former Secretary of State Hillary Clinton in the 2016 presidential election.

California is not the only state in which Sanders backers are trying to take over Democratic parties. The group is also organizing in Florida, Iowa, Colorado and Michigan, Jackson said.

“Hopefully, within a year or two, we’ll have a majority of the states covered,” Jackson said.