A federal appeals court on Friday ruled that hundreds of thousands of felons in Florida who still owe fines and fees may not register to vote, making it unlikely that they will be able to cast ballots in the upcoming presidential election.

The U.S. Court of Appeals for the 11th Circuit in Atlanta agreed with Florida Gov. Ron DeSantis, a Republican, that the payment of fines and fees by ex-felons is part of their "terms of sentence" and must be satisfied before they can vote.

The decision comes less than a month before the presidential swing state's Oct. 5 deadline to register to vote for November's general election.

"This is a deeply disappointing decision," said Paul Smith, vice president at the Campaign Legal Center, one of the groups that had sued over the rule. "Nobody should ever be denied their constitutional rights because they can't afford to pay fines and fees."

The groups that filed suit say they are still deciding whether to appeal to the U.S. Supreme Court. Earlier this summer, the high court declined to overturn a lower-court decision that also went against felons seeking to register.

A spokesman for DeSantis lauded the decision. "Second chances and the rule of law are not mutually exclusive," Fred Piccolo said.

The decision in the populous swing state could have implications for the presidential election. In 2016, Donald Trump won Florida by about 1.3 percentage points, or fewer than 120,000 votes, and a recent NBC-Marist poll found that Trump and Democratic nominee Joe Biden are neck-and-neck in the state, each at 48%.

About 28% of the felons affected by the issue in Florida are Black. Expanding voting rights to historically disenfranchised groups is typically believed to benefit Democrats, but there is no statewide partisan breakdown of which party the newly registered felons selected, if any. Jared Kushner, a White House adviser and Trump's son-in-law, said on Fox News last year that "we've had more ex-felons register as Republicans than Democrats," but the research is unclear on that.

The legal fight stems from a constitutional amendment overwhelmingly passed by Florida voters in 2018 that allowed most felons to register to vote. The amendment overturned decades of practice in Florida, where felons had to petition the governor to have their rights restored.

The amendment affected an estimated 1.4 million adults in the state. Thousands began registering to vote beginning Jan. 8, 2019, the first day they were eligible to under the amendment. But six months later, DeSantis signed into law an extra requirement that all fines and fees owed by felons, such as restitution to victims, must be paid in full before they could register.

The circuit court's decision cites the language in the amendment — "to automatically restore the right to vote for people with prior felony convictions, except those convicted of murder or a felony sexual offense, upon completion of their sentences, including prison, parole, and probation" — to determine that the state is within its rights to demand that felons who owe money pay before they register.

"Every court to have analyzed the issue has reached the same conclusion: felons do not have a fundamental right to vote," Judge Barbara Lagoa wrote in a concurring opinion.

The decision calls the DeSantis bill "a legitimate exercise of Florida's power to set core voter qualifications."

The decision was authored by Chief Judge William Pryor, a George W. Bush appointee whom President Donald Trump openly considered for a Supreme Court vacancy in 2018.

Earlier this week, Trump added additional names to his public list of potential Supreme Court choices, among them Lagoa and another concurring judge in the decision, Kevin Newsom, a Trump appointee.

Voting rights advocates and many felons argued that the state has no system in place for people to find out what their debts are after they are released from prison.

Some state attorneys have created streamlined systems to help figure that out, and the Florida Rights Restoration Coalition has worked with pro bono attorneys to help "returned citizens" determine whether they owe any money.

But few new voters have resulted from those efforts. The FRRC, which helped get Amendment 4 passed, has paid $4 million to help 4,000 people pay their fines and register.

The effort to pay fines has attracted donations from names such as Michael Jordan and the Jordan Brand, which donated $500,000 to the FRRC, and More Than a Vote, which was co-founded by NBA superstar LeBron James and donated $100,000 to the group.

Researchers estimate that 85,000 former felons have registered to vote under Amendment 4. They will have to be screened by elections supervisors to ensure that they are eligible.

Desmond Meade, president of the FRRC, said the group's efforts would continue.

"We will not rest until we live up to the promise of Amendment 4 and see every one of the 1.4 million returning citizens who want to be a part of our democracy have the opportunity to do so," Meade said.