John Minchillo/AP Photo
The decision came after a September ruling in which a Cincinnati-based appeals court declared the removal of some 2 million qualified but inactive voters from the voter registration rolls illegal.
"If those who were unlawfully removed from the voter rolls are not allowed to vote, then the Secretary of State is continuing to to disenfranchise voters in violation of federal law," wrote Judge George Smith, who serves at the Southern District of Ohio.
Over the last several years, Ohio Secretary of State Jon Husted cancelled the registration of voters who did not update their registration or vote over six years, as well as removing deceased voters and duplicate registrations from the rolls. Voters removed are sent a confirmation form when they are removed.
The appeals court said in September that the forms provided do "nothing to correct the fact that Ohio has, for years, been removing voters from the rolls because they failed to respond to forms that are blatantly non-compliant."
Carlos Barria/Reuters
Voting rights groups has pushed to restore the voting rights of illegal purged voters, and even sued Ohio's elections chief. The state proposed to the district court to only allow a small amount of purged voters to vote.
The district court turned down the state's plan. The final decision lets anyone purged since 2011 and anyone who has moved within their county to vote.
Husted told The Cincinatti Enquirer that the state will abide by the decision.
"Our main concern was to protect the integrity of the election by not having to reinstate deceased voters, those who moved out of state, or are otherwise ineligible. We will fully comply with the judge's order to count votes of people who remain eligible in their original county and continue to focus on the important work of administering a smooth election," he said in a statement.
As early voting is underway in the crucial swing state, Hillary Clinton and Donald Trump are polling tightly, with Clinton slightly trailing Trump with 44% to 48%, according to new CNN/ORC polls.