The Federal Election Commission took its electronic filing system offline on Monday night after someone tried to break into the agency’s computers, with the Nov. 3 midterm elections a week away.

The shutdown means super PACs, campaigns and other groups can’t submit the 24-hour and 48-hour reports that show, close to real time, how much is being spent on specific races. Reports already on file can still be searched. FEC Notify, which emails subscribers when new filings come in, is down too.

“We have a bad actor attempting to breach FEC systems,” an FEC electronic filings officer wrote on Monday night in an email to several campaign compliance firms, as Reuters reported after seeing the message. The officer told the firms the agency had to “temporarily shut down” its web-facing services. Compliance officers had noticed late Monday when they couldn’t file required reports.

The agency’s status page logged an investigation into the outage at 10:15 p.m. Eastern time on Oct. 26, according to Nextgov/FCW. At 8:17 p.m. on Tuesday, the FEC said it had found the problem and was putting a fix in place. It didn’t say the work was done. An email obtained by Nextgov/FCW listed filing search features and report validation tools among the services still dark.

The system was still offline early Wednesday, CNBC reported.

In a statement, the commission said that “at this time, the FEC’s electronic filing system is currently offline and our IT staff are actively working to restore service.” It has not said who tried to get in, whether anyone succeeded or whether any data was compromised. The FBI and the Cybersecurity and Infrastructure Security Agency referred questions to the FEC, NBC News reported. Nothing made public so far ties the attempt to a government or a criminal group.

Steven Mele, the chief executive of MBA Consulting Group, a compliance firm, said: “I’ve never seen this in 26 years.” Until the system is fixed, Mr. Mele said, voters will get less disclosure about the elections.

The gap comes at the costliest stretch of the costliest midterms on record. Super PACs and dark money groups spent an average of more than $50 million a day over the past week. The 50 biggest contributors in the race have put in $2.77 billion, led by Elon Musk’s $446 million for Republican-aligned groups, Al Jazeera reported. Campaigns have also spent more than $80 million on AI ads this cycle.

The FEC enforces campaign finance law. It doesn’t run elections, and the outage has no bearing on whether people can vote.

Dara Lindenbaum, a Democratic commissioner, made the same point on X. “This has NOTHING to do with voter files or voter registration,” Ms. Lindenbaum wrote. “Those are maintained by the states.”