Republican megadonor Mercer family weighs backing Trump as they maintain massive war chest

One of the Republican Party's most influential families may come off the sidelines to financially support Donald Trump's latest White House run, after years of distancing themselves from him, according to people familiar with the matter.

Robert Mercer and his daughter, Rebekah, have not yet made a final decision on whether they'll publicly back Trump, these people said. But the Mercers remain friendly with key players in Trump's orbit, including former senior counselor Kellyanne Conway, according to some of the people, who spoke on the condition of anonymity to share details of the thinking of the notoriously private Mercer family.

The Mercers gave millions to a super PAC and other efforts to boost Trump in 2016, before very noticeably stepping back around 2018.

A representative for the Mercer family did not return a request for comment.

As they weigh their options on whether to get involved with helping Trump again, the Mercer family has a practically unparalleled private war chest ready to be deployed.

The Mercers came into the pivotal 2024 presidential election cycle with just more than $88 million stashed away in their private nonprofit, the Mercer Family Foundation.

If they decide to fund efforts to support Trump, like they did during the 2016 election, this money could provide critical resources for influential conservative political causes, according to experts who reviewed the documents.

"The Mercer Family Foundation is sitting on a huge endowment that can—and likely will—be directed towards pushing politics and policy to the extreme right," Brendan Fischer, a deputy executive director at special interests watchdog Documented, told CNBC after he reviewed the group's 990 tax return. 

The $88.4 million that the foundation amassed at the end of 2022 was in part due to a sale last year of more than $20 million in publicly traded securities and other holdings, according to the 990 tax forms reviewed by CNBC. The cash it had coming into 2023 was slightly down from a year earlier, as the foundation started last year with just over $96 million.

Robert Mercer, who was the co-CEO of hedge fund Renaissance Technologies, donated just over $6 million to the foundation in 2021, according to the group's tax records from that year. Though the foundation is solely funded by the Mercers, there were no donations made by the family to the organization last year, according to the new documents.

The Mercers have a history of supporting conservative causes, including becoming part owners of the conservative news site Breitbart.

While the Mercers have largely disappeared from public view since helping Trump win in 2016, they have continued to try to wield influence in Republican political circles with their money, including through the family foundation.

Last year they gave $31 million to the DonorsTrust, a 501(c)(3) donor advisory fund that funnels money to often right-leaning causes on behalf of its clients. This was the most the Mercer Family Foundation has ever recorded giving to any group through its charity organization, according to data from ProPublica's database.

Rebekah Mercer was an investor in the now shuttered Parler that was supposed to be a social media space for conservative voices.

She is also a reported co-founder and investor of 1789 Capital, a financial firm run by Wall Street veteran Omeed Malik that led a $15 million seed round into a new media company owned by former Fox News host Tucker Carlson and his longtime business partner Neil Patel, according to the New York Post and The Wall Street Journal.

Rebekah Mercer is also part of a coalition of Republican donors called the Rockbridge Network, which includes fellow GOP financier Peter Thiel, according to The New York Times.

Experts who reviewed the tax documents say that the family could donate as much as they want from their foundation's assets to politically focused organizations that could impact the upcoming election.

Shanna Ports, senior legal counsel for the watchdog Campaign Legal Center, told CNBC in a statement after reviewing the 990 that, even though 501(c)(3) charities are barred from "directly intervening in elections or supporting candidates," such organizations "can still undertake a range of activities that impact elections."

That includes funding voter registration and get-out-the-vote drives, financing litigation efforts, taking positions on public policy issues, making contributions to fund down-ballot measure committees or assisting with programs run through more politically engaged nonprofit groups that do not have to publicly list the names of their donors, according to Ports.

"A charity like the Mercer Family Foundation, with over $88 million at its disposal, could have an outsized impact on the 2024 election by participating in those sorts of activities," Ports told CNBC.

Contributors to the DonorsTrust, for instance, have their money funneled to desired causes, without the public ever knowing the original source of the funds since it does not publicly disclose the names of its donors. The conservative-leaning FreedomWorks, the State Policy Network, the Constitutional Defense Fund and Project Veritas all received funds last year through DonorsTrust, according to the Center for Media and Democracy.

In 2021, the Mercer family donated just under $6 million to DonorsTrust, according their tax records from that year. In 2020, the year of the pivotal election that saw Joe Biden defeat Trump, the Mercer foundation gave around $20 million to DonorsTrust.

The DonorsTrust raised more than $300 million last year and lists an anonymous $31 million contribution on its 2022 990 forms, which could be from the Mercer family. It's the third-highest donation listed on DonorsTrust's most recent tax records.

Some of the top recipients from DonorsTrust in 2022 were the same conservative groups that the Mercer foundation has previously funded. DonorsTrust doled out more than $240 million in grants last year alone, according to its tax records.

Those groups that received millions from DonorsTrust last year include $7.9 million to the Oregon Institute of Science and Medicine, a nonprofit that rebukes the idea there is man-made climate change. DonorsTrust last year also gave $1.5 million to the Government Accountability Institute, an organization co-founded by longtime Mercer ally Steve Bannon and chaired by Rebekah Mercer herself.

The Government Accountability Institute is responsible for a litany of politically driven investigations. It was involved with probes of Hillary and Bill Clinton that led to the book by the group's president, Peter Schweizer, called "Clinton Cash: The Untold Story of How and Why Foreign Governments and Businesses Helped Make Bill and Hillary Rich."

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