Voters cast their ballots at the Water Tower during voting in Wisconsin U.S. presidential primary election in Milwaukee. (REUTERS/Kamil Krzaczynski)

Wisconsin voters will need to present an ID to cast their ballots in November, but the process for obtaining the right identification is likely to become easier, a federal appeals court ruled Friday.

The unanimous ruling by the U.S. Court of Appeals for the 7th Circuit seems to have resolved a months-long legal battle over Wisconsin’s law requiring voters to show photo ID when they vote, which will apply for the first time in a presidential race this fall. Critics have said the rule, like other similar laws across the country, will suppress minority and lower-income voters who tend to have more trouble obtaining photo IDs. Voting rights advocates momentarily scored a victory earlier this year when a lower court said that residents who could not easily get identification could alternatively sign an affidavit at the polls attesting to their identity.

Instead, Friday’s ruling means that voters will not be able to sign an affidavit. The court declined, though, to block aspects of a separate lower court decision that ordered the state to reform its process by which voters can get IDs at the DMV and to lift restrictions on early voting.

It is possible — though unlikely — that the 7th Circuit’s decision could be appealed to the Supreme Court. Dale Ho, director of the ACLU’s Voting Rights Project, said while his group was still trying to convince the 7th Circuit of the merits of allowing voters to use an affidavit instead of an ID, the case would now “probably not” affect the November election.

Rebecca Ballweg, a spokeswoman for the Wisconsin Department of Justice, called the ruling “a significant victory for the people of Wisconsin and ensures that Voter ID will be in place for the upcoming election in November.”

The appeals court wrote that lawyers for Wisconsin had assured the judges that voting credentials would be “available to all qualified persons who seek them” and that the state would not refuse to initiate a process known as “IDPP” to provide residents with IDs if they lacked proof of citizenship, a Social Security card or other documents.

The 7th Circuit, though, ruled that the state must “adequately inform the general public that those who enter the IDPP will promptly receive a credential for voting, unless it is plain that they are not qualified.” It said a district judge could monitor the state’s compliance.

Ho said he did not understand why — if voters could merely go to the DMV and attest to their identity to get an ID — they couldn’t do so to vote.

“They’re just adding on an administrative layer that’s going to make it harder for some people, even if it works perfectly, and we have every reason to believe that it’s not,” he said.