BUFFALO, N.Y. -- Eight years after casting his first ballot, Buffalo attorney TheArthur Duncan still relishes the moment, because it almost didn't happen.
He registered to vote shortly after getting out of federal prison and wasn't sure if he was even eligible to do so.
"When someone takes your freedom away and you get out of jail, and you think about all of the rights that was taken away," Duncan said. "Now you're like 'Well, now I got my freedom back' and you want to assert your rights and one of your rights as a U.S. citizen is to vote."
However, it's a right convicted felons don’t always have.
According to the New York Civil Liberties Union, there are more than 100,000 people of voting age in the state who will be barred from voting next month due to a felony conviction.
More than 5 million people nationwide face the same problem.
Each state has different laws about this. In New York, you can't vote if you are incarcerated or on parole.
Once that time is over, you must re-register to vote, but many released convicts don't know this and either don't vote, or have their ballots invalidated.
It’s a problem that Republican Erie County election commissioner Ralph Mohr says is more common than people think.
"We generally run into the situation where a person is released from jail, has finished his period of parole, has his voting rights eligible to be restored, but has not re-registered and then shows up to vote,” said Mohr.
It's why the NYCLU is working to educate anyone who has been through the justice system about their rights.
John A. Curr III, the NYCLU western regional director says the group will also run a "voter help hotline" come Election Day.
"Once you've served your debt to society, it should not endanger you or keep you from exercising your constitutional rights moving forward,” said Curr III.