Former President Donald Trump has officially endorsed a plan, created by a man who has self-identified with the Oath Keeper militia, that aims to have Trump supporters consolidate control of the Republican Party.

The plan, known as the “precinct strategy,” has been repeatedly promoted on Steve Bannon’s popular podcast. As ProPublica detailed last year, it has already inspired thousands of people to fill positions at the lowest rung of the party ladder. Though these positions are low-profile and often vacant, they hold critical powers: They help elect higher-ranking party officers, influence which candidates appear on the ballot, turn out voters on Election Day and even staff the polling precincts where people vote and the election boards that certify the results.

“Just heard about an incredible effort underway that will strengthen the Republican Party,” Trump said Sunday in a statement emailed to his supporters. “If members of our Great movement start getting involved (that means YOU becoming a precinct committeeman for your voting precinct), we can take back our great Country from the ground up.”

Trump’s email named Dan Schultz, an Arizona lawyer and local party official who first developed the precinct strategy more than a decade ago. Schultz spent years trying to promote his plan and recruit precinct officers. In 2014, he posted a callout to an internal forum for the Oath Keepers militia group, according to hacked records obtained by ProPublica.

“Why don’t you all join me and the other Oath Keepers who are ‘inside’ the Party already,” Schultz wrote under a screen name. “If we conservatives were to do that, we’d OWN the Party.”

Federal prosecutors in January charged the leader of the Oath Keepers and 10 of its other members with seditious conspiracy in last year’s attack on the U.S. Capitol. One of them pleaded guilty, as have several members of the group in related cases who are cooperating with the investigation. The group’s leader, Stewart Rhodes, pleaded not guilty.

There is no indication that Schultz had any involvement in the Capitol riot.

Schultz told ProPublica he never became a formal member of the Oath Keepers organization. “I have taken oaths to support and defend the Constitution as a West Point cadet, as a commissioned U.S. Army officer and as a practicing attorney,” Schultz said in a text message. “Those oaths do not have expiration dates, by my way of thinking, and I have kept my oaths. In that sense, I am an ‘oath keeper.’”

According to experts on extremist groups, the Oath Keepers recruit military and law enforcement veterans using the idea that their oath to defend the Constitution never expired. The group then urges people to resist what they say are impending orders to take away Americans’ guns or create concentration camps.

“I don’t ever want to be pulling the trigger on an AR-15 in my neighborhood,” Schultz said in a 2015 conference call with fellow organizers, referring to the semi-automatic rifle. “Oath Keepers, I love them for instilling the oath. But what they need to do also, I think, is spread the message that hey, we can do stuff politically so we never get to the cartridge box.”

In more recent interviews on right-wing podcasts and internet talk shows, Schultz has repeatedly described his precinct strategy as a last alternative to violence.

“It’s not going to be peaceful the next go-round, perhaps,” Schultz said in a June interview with the pro-Trump personality David Clements. “But it ought to be, and the way to ensure that it will be is we’ve got to get enough of these good decent Americans to take over one of the two major political parties.”

It was not clear whether Trump or his aides were aware that Schultz has self-identified with the Oath Keepers. Trump’s spokesperson, Liz Harrington, did not respond to requests for comment.

Schultz has spent months trying to get his idea in front of Trump. Steve Stern, a fellow movement organizer, told ProPublica that he met a former Trump administration official for lunch at Mar-a-Lago, the ex-president’s private club in Palm Beach, in December. While there, Stern said, he got a chance to briefly mention the project to Trump.

Then, last month, Schultz and Stern landed an interview on a talk show hosted by Mike Lindell, the MyPillow CEO who promotes conspiracy theories about the 2020 election. Lindell said he would discuss the plan with Trump personally. Schultz and Stern followed up with a conference call with Harrington and Bannon, according to Stern. Harrington previously worked at Bannon’s “War Room” website.

“I know the president’s very jacked up about it,” Bannon said on his podcast, speaking with Schultz after Trump released the endorsement. “Help MAGA, help the America First movement, right? Help the deplorables, help President Trump, help yourself, your country, community, your kids, grandkids, all of it. Put your shoulder to the wheel.”

Bannon, who led Trump’s 2016 campaign, originally lifted the precinct strategy to prominence in a podcast interview with Schultz last year. After the episode aired, thousands of people answered Bannon’s call to become precinct officers in pivotal swing states, according to data compiled by ProPublica from county records and interviews with local party officials.

As of last August, GOP leaders in 41 counties reported an unusual increase in sign-ups since Bannon’s first interview with Schultz, adding a total of more than 8,500 new precinct officers. The trend appears to have continued since then. New precinct officers started using their powers to remove or censure Republican leaders who contradicted Trump’s election lies and to recruit people who believe the election was stolen into positions as poll watchers and poll workers.

Bannon received a last-minute pardon from Trump after the former adviser was charged with financial fraud. He has pleaded not guilty to contempt of Congress for defying a subpoena from the committee investigating the Jan. 6 attack. Bannon’s spokesperson did not respond to requests for comment.

In addition to Bannon and Lindell, the precinct strategy has won support from pro-Trump figures such as former national security adviser Michael Flynn, who urged Trump to impose martial law, and lawyers Sidney Powell and Lin Wood, who led some of the lawsuits seeking to overturn the election results. Right-wing groups such as Turning Point Action, which organized buses to transport rallygoers on Jan. 6, also joined the effort to recruit precinct officers.

While Stern said he’s thrilled about Trump’s written statement endorsing the precinct strategy, he said he hopes to hear it from Trump’s own lips at an upcoming rally. Stern said he plans to be there with tables to sign more people up.