Big four super PACs focused on control of Congress raised $71 million in dark money last year

The four main super PACs focused on helping Democrats and Republicans win House and Senate elections raised a combined $71 million from affiliated dark money sources in 2025, according to an Issue One analysis of campaign finance reports.

That’s up by roughly 65% from how much money these four super PACs collectively raised from anonymous sources at the same point during the 2022 and 2024 election cycles.

“Voters of all parties lose when wealthy donors and special interests use huge dark money contributions to buy access and influence with lawmakers,” said Issue One Director of Money in Politics Reform Michael Beckel. “When super PACs accept massive sums of dark money, it undercuts the principle of transparency that serves as the foundation of our anti-corruption laws.”

“The U.S. Supreme Court’s majority opinion in Citizens United envisioned a world in which disclosure rules enabled citizens to make informed decisions about the political ads they see and the messengers behind those ads,” Beckel continued. “Yet the reality of political spending today makes a mockery of the Court’s logic. Both political parties continue to escalate a fundraising arms race fueled by anonymous donors that shows no signs of slowing down. Republicans and Democrats alike should welcome reforms that end the scourge of secret spending in our elections.”

In 2025, about 75% of the dark money raised by these four super PACs flowed to the two main Republican-aligned super PACs — the Congressional Leadership Fund (which works to elect House Republicans) and the Senate Leadership Fund (which works to elect Senate Republicans and also goes by the acronym SLF PAC).

About 25% flowed to the two main Democratic-aligned super PACs — Senate Majority PAC (which works to elect Senate Democrats and also goes by the acronym SMP) and House Majority PAC (which works to elect House Democrats and also goes by the acronym HMP).

In 2025, the Republican-aligned Senate Leadership Fund saw a huge spike in dark money contributions, as Republicans seek to hold onto their majority in the Senate, while the Democratic-aligned Senate Majority PAC actually saw a drop in secret contributions. The two House-focused super PACs each saw steady growth in dark money contributions.

Put another way:

• About $1 of every $3 raised in 2025 by the Republican-aligned Senate Leadership Fund came from its affiliated dark money group, One Nation ($35 million).
• Nearly $1 of every $4 raised in 2015 by the Republican-aligned Congressional Leadership Fund came from its affiliated dark money group, the American Action Network ($17 million).
• Roughly $1 of every $6 raised in 2025 by the Democratic-aligned House Majority PAC came from its affiliated dark money group, Majority Forward ($11 million).
• Roughly $1 of every $7 raised in 2025 by the Democratic-aligned Senate Majority PAC came from its affiliated dark money group, Majority Forward ($8 million).

As Election Day 2026 nears, these percentages are likely to change, as super PACs can raise unlimited amounts of money from a variety of sources. During the 2023-2024 election cycle, each of these four super PACs raised about $1 of every $5 of their respective funds from affiliated dark money groups.

During the 2024 election cycle, the Republican-aligned Senate Leadership Fund raised $299 million — 21% of which came from its affiliated dark money group, One Nation ($64 million).

And the Republican-aligned Congressional Leadership Fund raised $243 million during the 2024 election cycle — 18% of which came from its affiliated dark money group, American Action Network ($43 million).

All the while, the Democratic-aligned Senate Majority PAC raised $390 million during the 2024 election cycle — 21% of which came from its affiliated dark money group, Majority Forward ($82 million).

And the Democratic-aligned House Majority PAC raised $260 million during the 2024 election cycle — 18% of which came from its affiliated dark money group, House Majority Forward ($47 million).

Dark money flowing to super PACs also played a major role in the 2024 presidential election.

A pro-Donald Trump dark money group called Securing American Greatness invested more than $67 million into pro-Trump super PACs during the 2024 election cycle, including more than $52 million into the Make America Great Again Inc super PAC, a sum that represented about $1 of every $8 the super PAC raised.

The identities of just four donors to Securing American Greatness are known, as Issue One uncovered last month, including an advocacy organization associated with the cryptocurrency industry that gave $2 million.

Meanwhile, Future Forward PAC, the main super PAC supporting Democratic presidential nominee Kamala Harris, raised $266 million from its associated dark money group, Future Forward USA Action — a sum that represented nearly half of the super PAC’s total $559 million war chest.

According to reporting by the New York Times, donors to Future Forward USA Action include billionaires Michael Bloomberg (the former mayor of New York City) and Bill Gates (the co-founder of Microsoft) as well as a philanthropic organization associated with billionaire investors George and Alex Soros.