Rep. Tom Tiffany, R-Wis., called for an investigation after Madison officials reported sending out 2,215 duplicate ballots across 10 wards.
Officials say the ballots have identical bar codes, preventing double counting.
“The City of Madison clerk said the duplicates were sent to one ward,” Tiffany posted on X. “Now it’s 10. An independent investigation is needed now, not after the election.”
Tiffany’s office pointed out that the initial report of one ward later expanded to 10, showing a shift in the city's story.
“This can’t be ignored,” Tiffany told Fox News Digital. “Those responsible must be held accountable.”
In 2020, President Biden won Wisconsin by fewer than 21,000 votes, a crucial battleground state.
Madison Deputy Clerk Jim Verbick called it a human error, affecting voters with the same style ballots, according to WKOW.
Tiffany demanded "answers and transparency" in a letter to the city clerk, citing Madison’s controversial election history.
Dylan Brogan, a city spokesperson, confirmed the mistake but emphasized that no duplicate ballots would be counted.
Brogan explained that the duplicate ballots were the result of a data processing error, but identical bar codes ensure only one ballot can be counted.
Additionally, voters are marked in the system after submitting a ballot, preventing a second from being counted.
Brogan said the issue was due to two files being merged incorrectly, causing up to 2,000 duplicate ballots to be mailed.
The city has been contacting voters to ensure they only submit one ballot.
Despite the error, Madison has taken steps to correct it, notifying voters and ensuring only one vote per person will be counted.
Verbick reassured voters that submitting two ballots would not result in both being counted, urging them to destroy the duplicate.
When asked about Tiffany's letter, Verbick stated the office has been transparent about election matters.
No third-party investigation is planned at this time.
Brogan told the Associated Press that Clerk Maribeth Witzel-Behl is responding to Tiffany's concerns.
As of Monday, none of the 27,421 absentee ballots sent had been returned, including the duplicates.