Hedge fund manager Stephen Mandel and his wife Susan are a billionaire power couple that has a history of springing into action come election season. Before the 2024 presidential contest, they hosted Joe Biden for a private fundraising dinner in Greenwich, Connecticut. Kamala Harris, Hillary Clinton, and John Kerry are other beneficiaries of the $84 million that the Mandels have sprinkled to Democratic campaigns over time, according to Federal Election Commission records.

Now, the couple is gearing up for the 2026 midterm elections.

The Mandels have given almost $10 million in support of Democrats seeking federal office this year, federal records show, with more expected. 

"They are extremely influential and generous supporters who have never asked for very much," one veteran Democratic fundraiser who has worked for half a dozen presidential campaigns and interfaced with the couple told CBS News. 

The Mandels' giving offers a window into how billionaire megadonors have become an unrivaled force in American politics. The ultra-wealthy donor class is preparing to pour resources into an election that will decide whether Republicans or Democrats have a majority in the next Congress. 

In 2024, ultra-wealthy donors poured more than $3 billion into elections, led by the world's richest man — Elon Musk. He spent more than $290 million supporting President Trump and other Republicans, a record sum. And overall, that $3 billion was spent overwhelmingly to benefit the GOP — these donors gave five times as much to Republicans and groups aligned with them as they did to Democrats. 

That trend appears to be continuing: Republican Party committees, super PACs, MAGA Inc. and other Trump-related groups had over $600 million in cash on hand in early February, while Democratic Party committees and congressional super PACs were short of $200 million.

Election spending has ballooned in the decade and a half since a Supreme Court ruling that opened the floodgates for corporations and unions to donate without any limits. Billionaires on both sides have funded a constellation of opaque political organizations, raising fresh questions about "dark money" and lax disclosure laws, as well as, in some cases, whether groups are complying with rules on the books.

The structures and cash flow of these organizations — which operate on both sides of the political aisle — have taken on a new level of complexity, even for the already serpentine world of campaign giving. 

After the 2024 election, the Majority Democrats PAC was launched by centrist Democrats to recruit new candidates and challenge the party's more progressive wing. 

The Mandels, along with Mark Heising — a billionaire investor in San Francisco who also fundraises for Democrats — are top funders of Majority Democrats PAC. More than 90% of its publicly disclosed fundraising haul since last July is traced to more than $7 million in contributions from the Mandels and roughly $1 million from Heising.

Majority Democrats PAC fundraises alongside another political committee called The Bench, which says on its website that it "is recruiting and supporting the next generation of Democratic leaders." 

Personnel overlap between the two committees makes it hard to determine who is being paid by whom, experts said, noting that some of the same consultants who have been identified in news reports as working on behalf of Majority Democrats have also been quoted in the press as being affiliated with The Bench. They have also been identified as advisers to two Democratic senate candidates: Mallory McMorrow in Michigan and James Talarico in Texas.

Federal records do not list any payments from these two PACs to the consultants. But there are direct payments from the McMorrow and Talarico campaigns to the consultants for "communications consulting."

Caleb Burns, a partner at law firm Wiley Rein and the co-chair of its election law and government ethics practice, said the rules allow consultants to wear multiple hats, but told CBS News "the consultants must take great care to ensure their work for one client is not paid for or subsidized by another."

At the heart of federal campaign finance law are rules designed to protect the democratic process and ensure transparency. They strictly prohibit campaigns from coordinating with PACs on spending that should be made independently, or from the two covering each other's expenses. 

Burns said firewalls might be needed to make certain campaigns and fundraising committees aren't sharing non-public information.  "Otherwise, in-kind contributions can result that are subject to reporting and, potentially, prohibited," he added.

But the Federal Election Commission has always been slow to act on allegations of campaign finance violations, and now the commission isn't acting at all. The six-member commission is down to two and has lacked the four members it needs for a quorum since May 2025. Although Mr. Trump nominated two members in February, they have not yet been confirmed by the Senate.

Laws governing political parties' spending in coordination with federal candidates could be changing in the next few months, since the Supreme Court is expected to rule by June on the legality of the caps.

Officials with the Democratic committees told CBS News they comply with all federal regulations. A Majority Democrats spokesperson said the group "advises officeholders and candidates on strategy, press, and messaging" and "does not spend funds on paid communications that support or oppose candidates."

A spokesperson for The Bench said it "has in place a strict firewall policy adhering to all the correct statutes." The Talarico campaign declined to comment, and the McMorrow campaign did not respond. 

Myles Martin, a spokesman for the Federal Election Commission, said it "cannot comment on any potential enforcement matters that may come before the commission." The Department of Justice did not respond to requests for comment. The Mandels did not respond to requests for comment, nor did Heising.

"Battle plans"

David Dulio, who teaches campaign finance as the director of the center for civic engagement at Oakland University in Michigan, characterized the Majority Democrats arrangement as "another look into the mysterious and murky world" of campaign finance. 

Both parties participate. Republican spending aimed at the midterm elections may include significant infusions from President Trump's super PAC, MAGA Inc. Wealthy donors have contributed significantly to the organization's $300 million haul since the 2024 election, federal records show — a record-breaking sum. It has raised 96% of the funds from donors who gave $1 million or more, while 62% came from donors who gave at least $5 million, according to a report by the Brennan Center for Justice. 

Alex Pfeiffer, a spokesman for MAGA Inc., told CBS News that the group "is committed to retaining and building the GOP majorities in the House and Senate," but he declined to share what he referred to as its "battle plans." 

The largest donors to MAGA Inc., have included Republican billionaires Jeff Yass, a Pennsylvania-based investor, energy executive Kelcy Warren, as well as OpenAI President Greg Brockman and his wife, Anna Brockman, federal records show. It also has received at least $88 million since July 2024 from Securing American Greatness, a Trump-aligned nonprofit that is not required by the IRS to disclose its donors. 

Other influential super PACs underscore the heightened questions about dark money and billionaire influence — including one called Texans for a Conservative Majority that supports Republican Texas Senator John Cornyn. The single largest contribution that the PAC has received was $3.1 million from a nonprofit listed as Ohio Works — which said on federal filings that its address was a Parcel Plus shipping and mailing store in Alexandria, Virginia. 

In December of last year, just two weeks after the donation was disclosed, paperwork was filed in Ohio by an Ohio Works official changing its name to America Works Fund. 

Adding to the mystery, the name of the nonprofit matches that of another organization that saw its tax-exempt status revoked after failing to file financial disclosures, as well as its corporate status canceled in 2022 by the Ohio secretary of state. A year later, in 2023, that group found itself roped into a Federal Election Commission investigation about dark money spending after a complaint was filed by Citizens for Responsibility and Ethics in Washington, or CREW, a progressive nonprofit. The Federal Election Commission deadlocked 3 to 3, along party lines, on moving forward on enforcement of the complaint.

A spokesperson for Texans for a Conservative Majority did not respond to requests for comment. 

"When an opaque entity that is not required to disclose its own donors gives millions to a super PAC, it significantly impedes the public's ability to know who is spending significant sums to benefit — and potentially influence — elected officials," Matt Corley, CREW's chief investigator, told CBS News.

Corley said it is "even more difficult when the intermediary organization shapeshifts by changing its name."

Who are other top donors to Texans for a Conservative Majority? A cadre of billionaires, according to federal records: Blackstone CEO Stephen Schwarzman, Walmart heirs S. Robson Walton and Jim Walton, and Alex Karp, the CEO of software firm Palantir. 

To critics, this kind of tangled spending dynamic reflects an increasingly secretive web of money built to covertly distribute money from billionaire donors. 

It is part of what Craig Holman, a Capitol Hill lobbyist on ethics and campaign finance rules for the progressive nonprofit Public Citizen, called the "breakdown of campaign finance laws." 

"Despite contribution limits and disclosure requirements on the sources of campaign money, wealthy interests — and billionaires in specific — are exploiting influence-peddling avenues around these laws," Holman said.