A federal court case from Maine now headed to Boston could decide the future of campaign finance in America. At stake is whether the government can limit how much any one person can give to a super PAC, a ruling that could either upend the way modern campaigns are funded or cement the current system for good.

The first brief is due at the Boston-based US Court of Appeals for the First Circuit on Wednesday.

But advocates for campaign finance reform hope the next stop could be the US Supreme Court.

The Maine law at the center of the case limits contributions to any super PAC to $5,000 per donor. If upheld, it would replace the current system that allows unlimited contributions to groups supporting or opposing candidates, as long as they don’t coordinate directly with campaigns. The case will determine whether such limits violate the First Amendment or whether states can once again place guardrails on the flow of big money into politics.

In 2021, a Canadian power company spent $42 million using a super PAC to earn the rights to build a corridor of power lines connecting a hydroelectric power plant to the New England power grid via Maine’s hinterlands, one of the state’s most high-profile and controversial projects in recent memory.

The effort ultimately failed, but residents, alarmed at the sheer number of dollars pumped into the attempt, passed two different referendums to head off any similar efforts in the future.

One, passed in 2023 with 86 percent of the statewide vote, banned any company in which a foreign government owns at least 5 percent from donating to any state or local ballot measures. Further, it required media outlets to add a disclaimer about the foreign government investment on any ads those companies buy.

It was soon challenged by pair of super PACs from the political right, one of which has been actively supporting an unrelated referendum in Maine this fall. With help from lawyers at the Washington-based Institute for Free Speech, these super PACs got the 2023 law struck down as an unconstitutional measure against free speech by the First Circuit Court of Appeals in Boston.

In the wake of that came the law being questioned today. In 2024, 75 percent of Maine voters approved a referendum that limited contributions by anyone to a super PAC to just $5,000. Previously, there wasn’t a limit.

In July 2025, a federal judge in Maine struck down that law, citing a 2010 ruling by the District of Columbia Court of Appeals, SpeechNow.org v. Federal Elections Commission, which allowed super PACs to raise and spend unlimited amounts of money as long as they didn’t directly coordinate with a candidate’s campaign. Since 2010, super PACs have become a dominant staple of how presidential campaigns work and how wealthy individual donors attempt to wield more power over American politics.