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A "coding oversight" in state software is calling into question the citizenship status of 100,000 registered Arizona voters, prompting the state's Democratic secretary of state to insist he will send out ballots to those affected anyway.

"I am unwilling to disenfranchise this many voters by limiting them, suddenly, and with little notice, to a federal-only ballot when none of them had actual notice of or blame for this issue," Secretary of State Adrian Fontes said during a Tuesday news conference. "We inherited this problem, we're on it, and we're going to fix it. It's as simple as that."

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Person voting

A voter casts a ballot at a polling location in Fairfax, Virginia, on Nov. 7, 2023. (Tierney L. Cross/Bloomberg via Getty Images)

The mistake affects individuals who obtained their driver’s licenses before October 1996 and subsequently received duplicates before registering to vote after 2004. Since 2005, Arizona has required proof of U.S. citizenship for voting in state and local elections. Without this proof, these voters would be considered "federal only" voters, permitting them to vote solely on presidential and congressional elections rather than the full ballot.

"We don't have any reason to believe that anyone in this gap is not an eligible voter," Fontes said. "We don't have any reason to believe that they're not eligible citizens in spite of the fact that we did find one. All we know is they fit into this category and all of this requires more research."

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rolls of I voted stickers on display

Rolls of "I Voted" stickers are stored at the Maricopa County Tabulation and Election Center in Phoenix, Arizona, on June 3, 2024. (Patrick T. Fallon/AFP via Getty Images)

The Maricopa County Recorder's Office filed an emergency petition requesting the Arizona Supreme Court determine whether voters affected by the data oversight should be required to prove U.S. citizenship before the November election.

Fontes said the error comes as longtime Arizona residents have been voting in elections for years under the impression that they had already provided proof of citizenship. And if the justices determine these individuals are only eligible to vote in federal races, Fontes said there will be an outreach effort to inform them.

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Adrian Fontes, Arizona's secretary of state

Arizona Secretary of State Adrian Fontes during a House Administration Committee hearing on confidence in elections on Sept. 11, 2024, in Washington, D.C. (Bonnie Cash/Getty Images)

The error comes as Arizona Republicans and a conservative watchdog group have been pushing for stricter voting measures that require proof of U.S. citizenship to participate in state and national elections. Arizona is also a swing state that flipped blue in the 2020 presidential election. 

Last month, watchdog group America First Legal sued 15 Arizona counties for allegedly refusing to remove thousands of illegal immigrants from its voter rolls. The lawsuit claims that, as of April 2024, over 35,000 registered voters in Arizona had not provided proof of citizenship, limiting them to voting only in federal races, according to the Arizona Secretary of State’s Office.

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For their part, U.S. House Republicans are also attempting to attach H.R. 8281, which mandates proof of citizenship for voter registration and was passed in July, to a temporary government funding bill.

Neither of Arizona's U.S. Senate candidates, Republican Kari Lake and Democratic Rep. Ruben Gallego, responded to requests for comment by publication deadline.

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