MIAMI (CBS4) – In a new crackdown, Florida officials are investigating the citizenship of thousands of registered voters. CBS4 News has learned 2,000 of those potential non-citizen voters are registered in Miami-Dade County. At least one person on the list has had the opportunity to vote for the past 40 years.

“These are the people that we have to notify by mail that we have a reason to believe that they’re a non-citizen,” said Christina White, Deputy Supervisor of Elections.

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Miami-Dade is not alone. Broward is looking at 260 registered voters and Monroe is investigating four.

A CBS4/Miami Herald analysis of a partial list provided by Miami-Dade shows a large number of the suspect voters have cast ballots in the past. The party affiliations seem evenly split. The analysis of 350 people shows one person voted at least 30 times.

According to the analysis of the data, some of the potential non-citizens voted in the 2000 election, that’s when the presidency was decided by just over 500 votes.

“So it’s very important that voter registration rolls are accurate and only people who are eligible, are able to vote,” White told CBS4′s Gio Benitez.

Each person has 30 days to respond to the County’s inquiry asking them to prove their citizenship. Up until recently, no proof of citizenship was required when registering to vote.

“So, if we find out after the fact that you are actually a non-citizen, and you are registered to vote, then we would report you to the State Attorney’s office,” said White.

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The State Attorney may charge anyone unlawfully registered to vote with a felony.

“So if you are not [a citizen] and you check the box on the registration form that says that you are [a citizen], we are required to register you to vote, because you are taking that under oath.”

Broward Supervisor of Elections Brenda Snipes supports the investigation of non-citizen voters.

“As someone who has to uphold the laws of the state of Florida for elections, it’s totally inappropriate for that person to have been voting, if that’s the case,” said Snipes.

White says, in Miami-Dade, the potential non-citizen voters are a small percentage of the 1.2 million registered voters in Miami-Dade.

“So I don’t want to send an alarming message that we have a lot of non-citizens on our registration rolls,” she said.

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