Ex-convicts in the United States are fighting state restrictions that will effectively prevent 3.9 million people with a felony conviction from casting a vote in the November elections.

Several states have made recent changes to their laws that make it easier for ex-cons to vote. Connecticut, Texas, New Mexico, Maryland and Delaware will allow nearly 500,000 felons to vote this November.

But former inmates said that varying laws in each state could end up taking away restored rights.

Speaking at the National Symposium for Felony Disenfranchisement Monday, Thomas Johnson said his voting rights were restored in one state following his imprisonment, but denied to him when he moved to another state.

"I've changed my life and I'm a productive citizen, yet I feel that I'm without citizenship," said Johnson, 54, who served time in New York for selling crack cocaine and carrying a loaded handgun. His rights were restored in New York, but when he moved to Florida and tried to vote, he was told he would have to apply for clemency if he wanted to cast a ballot.

"I said, 'What for? I've never committed a crime in Florida,'" said Johnson, who is now the executive director of House of Hope, a program helping ex-cons get housing, jobs and counseling in Gainesville.

Each state makes its own laws regarding voting privileges for inmates and for those who have already served their time in prison.

Only Maine and Vermont allow inmates convicted of a felony offense to vote. Eighteen states take away voting rights for inmates convicted of any crime. States' laws regarding whether inmates get their rights back after serving time run the gamut.

A felony crime includes murder, rape, larceny and drug offenses.

Not everyone believes that states should be attacked for allowing those convicted of these crimes to participate in the process. Todd Gaziano, director of the Heritage Foundation legal and judicial studies department, said allowing inmates and felons to vote dilutes the vote of law-abiding citizens.

"It helps prevent dilution of the vote of law-abiding citizens who are in high-crime neighborhoods where law enforcement issues are of a particular importance," he said. "It's part of the original punishment. It's not arbitrary. It's on the books."