A mayoral campaign's website left Chicago voters' addresses and voting histories open to download, Illinois Answers reports

The campaign website of Chicago mayoral candidate George Cardenas exposed voter records for what appeared to be every registered voter in the city, including home addresses, birth years and which party's primary ballot each person chose in recent elections, the Illinois Answers Project reported in a story republished Thursday by Block Club Chicago.

Why it matters: roughly 1.5 million Chicagoans' information was reachable by anyone who knew where to look, according to the report. It's unclear how long the files were public or whether anyone downloaded them. Voter files are given to campaigns under state rules meant to keep that information from being spread around, and the exposure included judges, whose addresses state law specifically protects.

What the reporting found

According to the Illinois Answers report:

• A password for a campaign worker dashboard was visible in the website's public source code.
• The full dataset could be downloaded from the site's public file directory, with no protection behind it.
• Reporters told the campaign in early September. The login page was down by Sept. 3, and the voter data was removed a few days later.
• Cardenas, a Cook County Board of Review commissioner and former 12th Ward alderman, said he would fix it and called it "a programming glitch." The campaign did not respond to later requests for comment, the report said.

The report also said tools flagged text on the site as AI-generated, which Cardenas denied using. No law bars campaigns from using AI tools.

What the law says

Political committees that request voter data must agree to use it only for a "bona fide political purpose," according to the report, though the form doesn't spell out penalties for publishing it. A 2024 change to state law banned using voter roll data for "any personal, private or commercial purpose." That change followed a case in which Attorney General Kwame Raoul sued a publisher that had posted voter information across a network of websites. The case was settled, and the company admitted no wrongdoing.

The Illinois Answers report did not include a response from the Chicago Board of Election Commissioners or say whether any agency is reviewing the exposure.

What our records add

Where Cardenas stands in the race. The Board of Election Commissioners' candidate filing report lists Cardenas among six mayoral candidates stamped at 5 p.m. on Oct. 26, the close of filing, as we reported Wednesday. Those six will go into a lottery for their place at the bottom of the ballot. His campaign committee, CARDENAS4CHICAGO, registered with the State Board of Elections on May 4, 2026, according to the committee list on our mayor's race page. We have not yet received the Board's copy of his nominating papers, so his petition isn't on our candidate pages yet.

Like every candidate, he faces the objection window. Through Monday, Nov. 2, any registered voter can challenge a candidate's nominating papers at the Board's office, 69 W. Washington St., Suite 800, the Board said. Our objections page lists challenges once the Board publishes them; as of Thursday morning it lists none.

How we handle petitions. Nominating petitions carry the names and addresses of the voters who signed them. Our listing criteria say we don't publish them; our pages show only page counts and our tally of filled-in lines.

If you're a Chicago voter

• State rules give political committees access to voter files for political purposes, and the 2024 law bars using them for personal, private or commercial purposes.
• You can check your own registration on the Board's website.

What's next

• Nov. 2: objections due.
• Dec. 17: the Board certifies the ballot.
• Feb. 23, 2027: Election Day.

Sources: Chicago Board of Election Commissioners: Candidate Filing Report (printed Oct. 26, 2026).