Former President Donald Trump spent last week stuck in New York City for the beginning of his hush money trial. But on Wednesday, between days in court, Trump made time to call into a secretive donor meeting back at his Mar-a-Lago club in Palm Beach, Florida, according to two people involved with the group who were in the room.

The event was hosted by the Rockbridge Network, an under-the-radar, new-age conservative group that sees itself as the leading edge of a changing Republican Party — and is putting tens of millions of dollars into building a fresh infrastructure to support it. 

Trump spoke to a room of about 250 attendees who lean more tech-populist than traditional, 20th-century right or left, having gravitated to the former president and the way he has shaken up the Republican Party. Trump was originally slated to be a guest speaker but was unable to attend in person due to his New York trial. Donald Trump Jr. ended up pinch-hitting for his father as one of the star in-person speakers, according to the two people in attendance. Trump’s co-campaign managers, Susie Wiles and Chris LaCivita, attended as well. 

The Trump campaign did not respond to questions about the event.

Rockbridge isn’t yet a brand name in Republican politics, in part because the group has been secretive since its founding in 2019. The exact number of dollars behind the group is also difficult to verify, but one of the sources in attendance last week who is familiar with the group’s operations told NBC News it is in the “high tens of millions.” And while some older GOP donor groups eschew Trump — the Koch network, for example, is staying out of the presidential race after endorsing Nikki Haley in the Republican primary, preferring now to focus down the ballot — Rockbridge is firmly aligned with Trump.

Rockbridge sees itself as a sort of anti-Koch network that can fill in the gaps the party hasn’t traditionally invested in. As the GOP went from middle- and upper-middle-class to more middle- and working-class, Rockbridge founders felt the GOP infrastructure didn’t shift to support and capitalize on that, the same source noted. While Democrats had labor unions organizing their blue-collar base, for example, Republicans didn’t have a mechanism to do the same.

The organization is the brainchild of Ohio Sen. JD Vance (before he was a senator) and Chris Buskirk, the publisher of the website “American Greatness,” a pro-Trump outlet that describes itself as “the leading voice of the next generation of American Conservatism.” Billionaire Peter Thiel has been among those involved.

“All these other historical think tanks and more traditional conservative organizations didn’t capture the Trump movement at all and didn’t recognize the shift. Many are still operating like they’re in the 1990s,” said Omeed Malik, an entrepreneur and donor who has been involved with Rockbridge since 2022. 

Last week’s three-day gathering, which took place at the Palm Beach Four Seasons apart from the Wednesday night Mar-a-Lago event, featured both new- and old-school GOP donor stalwarts. Among the crowd was major GOP donor Rebekah Mercer, billionaire and former Trump ambassador to the United Kingdom Woody Johnson, and prominent conservative lawyer Leonard Leo, according to the two people present at the gathering. Also there were cryptocurrency luminary Erik Voorhees and former Uber exec Emil Michael. 

Rockbridge’s membership includes a number of people from the tech world and elsewhere who may not have given political contributions before, as well as more traditional donors on the right looking for new ways to invest their political money.

It’s not the first time Rockbridge has gathered at Mar-a-Lago. The group’s past events include a 2022 gathering at Trump’s club, The New York Times reported in a story detailing some of the network’s early plans.

One of Rockbridge’s big 2024 projects is voter registration. The group registered 125,000 voters in 2023 and is hoping to double that in 2024, according to the source at last week’s gathering who is familiar with Rockbridge’s operations. The organization is funding a program to target new registrants based on issues important to them and an “ambassador” outreach structure that sees ten new voters each assigned to one organizer who gets to know them.

New voters could be especially important to Trump in 2024 — the latest NBC News poll shows that Trump leads by a healthy margin among respondents who did not vote in 2020 or 2022. The question is whether those people will sign up and turn out. That’s where Rockbridge is hoping to come in. 

For people like Malik, the network also functions as an ideas exchange and generator. It was at a Rockbridge event in 2022 that the idea for Malik’s fund 1789 Capitol was hatched. It is now behind Tucker Carlson’s new media venture, with the fund leading financing for the former Fox News host’s latest venture.

Rockbridge’s standing in wider Republican circles is still murky. “Their name pops up at times, but it’s very unclear what their plan is for this cycle,” said one Republican operative who works with donors.

What is clear is that the network has the attention of Trump and his campaign — and it’s planning to play a big role in getting him elected again.