(CNN) A new state law takes effect in Florida Tuesday that is expected to restore voting rights to more than a million people with felony convictions -- despite questions from state officials about its implementation.

Supporters of the law say there's nothing ambiguous about Amendment 4, which was approved by nearly 65% of Florida voters in the November midterm elections.

The new law says voting rights shall be restored to those with felony convictions who complete all terms of their sentence, including parole or probation, except those convicted of murder or a felony sexual offense.

What constitutes completion of a sentence is shaping up to be a point of contention, along with other questions.

The president of the state association of elections supervisors said he and his counterparts have questions about how to implement Amendment 4. But in the meantime, nothing is stopping them from registering eligible voters, Okaloosa County Supervisor of Elections Paul Lux said.

"I haven't spoken to anyone who has plans to not register anyone starting tomorrow," Lux said, "but I wish we had better guidance."

How the law works

Starting Tuesday, eligible former offenders -- or returning citizens, as many preferred to be called -- will be able to register online or in person to vote just as any other Floridian would.

But it's on them to make sure they have completed all the terms of their sentence so they can honestly declare on a voter registration form that their right to vote has been restored.

In recent weeks, civil rights groups have ramped up outreach and education efforts to encourage those with felony convictions to register to vote. Completion of a sentence includes any period of incarceration, probation, parole and financial obligations imposed as part of a person's sentence, according to the coalition of groups that endorsed the legislation and is coordinating voter registration drives.

Financial obligations may include restitution and fines imposed as part of a sentence or a condition of probation under existing Florida statute, according to the coalition, which includes the American Civil Liberties Union of Florida

But Lux said none of that is spelled out in the newly revised statute. What if someone has not paid restitution? What if their court-ordered costs were converted into civil liens that are still outstanding? Has their right to vote been restored?

"We don't know because no one has specified it to us," he said.

He fears that the lack of specifics could lead to confusion or worse, such as someone registering to vote who has not completed the terms of their sentence, which could put an individual at risk of perjury.

He said it's also not clear how completion of a sentence will be reflected in the databases that election officials use to check someone's voter registration application. "I wont be able to provide guidance to these people because I don't know either," he said.

But the ACLU and other Amendment 4 supporters say it's not that hard to figure out if someone is eligible. And they encourage anyone who has questions to contact them.

"It's very clear and unambiguous on its face," Melba Pearson, deputy director of the ACLU of Florida, said of the law.

Will changes be needed?

Before Amendment 4 was passed, Florida was one of four states that permanently barred those with felony convictions from voting, and granted the governor the authority to restore voting rights, according to the Brennan Center for Justice

In Florida, the policy disenfranchised about 7% of the state's adult population, or nearly 1.5 million people, according to the Sentencing Project . The new law makes about 1.4 million of those people eligible to vote, according to groups that campaigned for Amendment 4.

"This is something about right and wrong and the ability to have a second chance and rebuild your life. And that's something that cuts across party lines. It cross cuts across gender and race," Pearson said.

One person who came out against the amendment before it passed was Florida's Republican candidate for governor, Ron DeSantis.

Now the incoming governor, DeSantis said in December that the law should not take effect until the legislature approved "implementation language." On Monday, DeSantis spokesman Dave Vasquez said the law will take effect Tuesday as planned, and then the governor "will look to the Legislature to clarify the various questions that have been raised."

The Florida Secretary of State's office confirmed that Amendment 4 will take effect Tuesday per the state constitution , which says approved measures should take effect after the first Monday in January following the election. Then, the department "will abide by any future direction from the Executive Clemency Board or the Florida Legislature regarding necessary action or implementing legislation to ensure full compliance with the law."

But the ACLU and others say they oppose "interference" from the legislature in the language of the law.

The amendment was written to be "self-executing" so its mandatory provisions could take effect on January 8, Pearson said. After DeSantis called for implementing language for the law in December, the ACLU and others sent a letter to the secretary of state asking it for guidance on how to conduct voter registration for the newly enfranchised population.

But the coalition stopped short of requesting changes to the statute, fearing any modifications could "interfere with the rights of the newly enfranchised people," Pearson said.

"We will be very vigilant with regards to the actions that result from this. And if we see that there are inequities in the process -- if we see that people are in fact having their right to vote suppressed -- we will take action as appropriate," Pearson said.

Lux said he and most county election supervisors don't dispute that the legislation is self-executing. But they are still waiting for some form of guidance, whether it comes from the legislature or an administrative body. Either way, he expects legal challenges may arise.

The good news? Even though municipal elections will start this year, the presidential primaries don't start until 2020.

"We've got time to work on it," Lux said.