The Federal Election Commission said Tuesday night that it identified the issue affecting its electronic filing system and was implementing a fix, after reports that a hacker or hackers had targeted the agency's systems days before the midterm elections.
But the system remained offline early Wednesday, cutting off a key window into campaign money just as late-election spending surges.
An FEC electronic filings official told campaign compliance firms Monday night that a "bad actor" was attempting to breach the agency's systems and that public-facing services had been shut down, according to an email obtained by Reuters. The filing system has been offline since around 10 p.m. ET Monday.
The FEC has not said who was behind the reported breach attempt, whether anyone gained access to its systems or whether any data was compromised. Previously filed reports remain searchable.
The FEC told CNBC that the agency's IT staff is working to restore the service.
In the final 20 days before an election, candidate committees must report certain contributions or loans of $1,000 or more within 48 hours, while political committees and outside groups must disclose certain spending within 24 hours.
Those rules are designed to give voters a near-real-time view of the money flooding into races when it matters most.
For example, Elon Musk's America PAC reported nearly $6.8 million in independent expenditures for communications disseminated Oct. 20, according to a CNBC analysis of FEC filings.
Spending on that scale normally becomes public almost immediately, but with the filing system down, new money can pour into races while the public stays in the dark.
The potential blind spot comes as the 2026 midterms become the most expensive U.S. election cycle on record by political advertising, with $11.21 billion spent or reserved as of Monday night, according to AdImpact.
Political committees and other outside groups reported nearly $610 million in independent expenditures for communications disseminated from Oct. 20 through Oct. 26 — an average of about $87 million a day — according to a CNBC analysis of FEC filings.
The outage also hits an already weakened agency. The six-member FEC, an independent agency that oversees campaign finance laws and has no role in administering elections, has had just two members since October 2025 and has lacked the four commissioners it needs to take official action since May 2025. Career staff have continued processing disclosures and running day-to-day operations.
The Cybersecurity and Infrastructure Security Agency and Federal Bureau of Investigation did not immediately respond to a request for comment.