Key Takeaways

  • Dark money flows through nonprofits organized under 501(c)(4) of the tax code, which can spend on political activity without publicly disclosing donors.
  • Following Citizens United, dark money in federal elections has grown from millions to billions of dollars per cycle.
  • Both parties benefit from dark money networks — Republicans through corporate-linked groups, Democrats through activist foundations and donor alliances.
  • The FEC and IRS have limited capacity or will to enforce donor disclosure requirements against well-lawyered nonprofits.

AI Summary

Key takeaways highlight Dark money flows through nonprofits organized under 501(c)(4) of the tax code, which can spend on political activity without publicly disclosing donors. Following Citizens United, dark money in federal elections has grown from millions to billions of dollars per cycle. Both parties benefit from dark money networks — Republicans through corporate-linked groups, Democrats through activist foundations and donor alliances. The FEC and IRS have limited capacity or will to enforce donor disclosure requirements against well-lawyered nonprofits.

Government

What Is Dark Money in Politics and Where Does It Come From?

April 28, 2026 · 3 min read

The simplest definition of dark money: it's political spending designed specifically so you can't see who's paying for it.

It is legal. It is massive. Both parties do it. And the people who would need to change the rules are the ones who benefit most from keeping them the same.

How the Architecture Works

The key legal vehicle is the 501(c)(4) nonprofit. These are "social welfare organizations" under the IRS code — think civic leagues and community groups. They are allowed to engage in political activity as long as politics is not their "primary purpose."

The IRS does not clearly define "primary purpose." Courts have not firmly defined it. In practice, a 501(c)(4) can spend close to half its budget on elections-related activity, run attack ads, fund voter mobilization, and support specific candidates — all without ever publicly reporting who donated the money.

Super PACs — which must disclose donors — can receive money from 501(c)(4)s. The 501(c)(4) reports that it made a donation to a super PAC. The super PAC reports receiving it. But neither report reveals where the 501(c)(4) got its money. The donor is invisible.

This creates a legal laundering architecture: wealthy individuals or corporations give to a 501(c)(4), which gives to another 501(c)(4), which gives to a super PAC, which runs ads. Tracing back to the original donor requires forensic accounting that regulators don't do.

The Koch Network and Its Democratic Counterpart

The most extensively documented dark money infrastructure in American politics was built by Charles Koch and his late brother David. The Koch Network — a constellation of interconnected nonprofits centered on organizations like Americans for Prosperity — funneled hundreds of millions into conservative candidates and causes, helping flip state legislatures, fund anti-climate-science campaigns, and shape Republican primary politics.

The Kochs spent decades building this infrastructure while publicly celebrating the value of free markets and private enterprise. The irony that their political dominance depended on legally hiding the influence they were purchasing was apparently not a concern.

Democrats have built comparable infrastructure. The Sixteen Thirty Fund, run by the firm Arabella Advisors, serves as a "fiscal sponsor" for dozens of liberal dark money nonprofits, allowing them to operate under an umbrella without fully independent nonprofit status. The Sixteen Thirty Fund received over $1.5 billion between 2019 and 2021 alone.

George Soros and his affiliated Open Society Foundations have spent billions on liberal causes through nonprofit structures that, while more transparent than some, still provide tools for political influence. Democratic politicians who decry dark money while benefiting from this network are engaging in the same hypocrisy they criticize.

Why Reform Fails Every Time

The DISCLOSE Act — which would require 501(c)(4)s to disclose donors above a threshold to the FEC — has passed the House under Democratic control and has failed every time in the Senate due to Republican filibusters. (Republicans, who currently benefit more from dark money totals, argue it infringes First Amendment rights.)

The Supreme Court's 2021 decision in Americans for Prosperity Foundation v. Bonta made state-level disclosure requirements harder to enforce.

The FEC, which is supposed to regulate campaign finance, has six commissioners — three Democrats, three Republicans — by law. It deadlocks constantly. It has limited enforcement staff and enormous caseloads. When it does find violations, fines are typically small fractions of the money involved.

The result is a system where the rules against disclosure have no meaningful enforcement, the politicians who could change the rules benefit from keeping them, and billions of dollars flow into elections from sources voters have no way to identify or evaluate.

You can know that an ad attacking a candidate was paid for by "Citizens for American Values." You cannot know that Citizens for American Values is funded by a hedge fund manager who has $50 billion in tax exemptions riding on the specific policy the ad is designed to influence.

That is the point.

FAQ

What is dark money in politics?

Dark money refers to political spending where the original source of funds is not publicly disclosed. It primarily flows through 501(c)(4) "social welfare" nonprofits, which can engage in political activity as long as it is not their "primary purpose." These groups can run attack ads, fund campaigns, and influence elections without ever disclosing their donors to the public. They can also donate to other nonprofits, creating chains of untraceable transfers.

How much dark money is there?

Estimates are inherently imprecise because the money is designed to be untraceable. The nonpartisan Center for Responsive Politics estimates hundreds of millions to over a billion dollars in dark money flowed into federal elections in recent cycles. The actual total may be higher because some spending is structured to avoid FEC reporting thresholds entirely. Citizens United (2010) dramatically increased dark money flows by opening the door to unlimited independent political spending.

Who uses dark money more — Democrats or Republicans?

Both parties use dark money extensively. Republicans have historically had a larger dark money infrastructure, built around groups like the Koch Network, US Chamber of Commerce, and affiliated nonprofits. Democrats have built their own dark money networks through groups like the Sixteen Thirty Fund and associated donors. Recent cycles have seen Democratic dark money grow substantially. Any politician claiming to oppose dark money while benefiting from it is being hypocritical, which describes most of them.

Can dark money be stopped?

The DISCLOSE Act — legislation requiring disclosure of donors to politically active nonprofits — has passed the House multiple times and failed in the Senate due to Republican filibusters. A constitutional amendment overturning Citizens United would require two-thirds of Congress and three-fourths of states. The FEC, which has six commissioners (three from each party), typically deadlocks on enforcement questions. Meaningful dark money reform faces nearly insurmountable political obstacles because the beneficiaries of the current system make the rules.

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