One of the most critical battleground states in the presidential election is home to three disputes over voting issues that could affect when voters can start casting ballots and how ballots will get counted this fall.
Groups have challenged Ohio's reduction to early voting, its ballot procedures, and its process for removing voters from its registration rolls.
Here's a look at the lawsuits in Ohio:
A dispute over a law that trims a week of early voting is headed to the U.S. Supreme Court.
The state's Democratic Party asked the court on Sept. 1 to suspend a ruling that would trim early voting opportunities.
That lower court decision from last month upheld a law eliminating days in which people could register and vote at the same time, a period known as "golden week."
The odds that the high court will side with the Democrats are pretty long.
The Supreme Court justices divided 4-4 on Aug. 31 on a move to reinstate North Carolina's voter identification requirement. The split illustrates how closely divided the Supreme Court is on voting rights.
Democrats allege the change disproportionately burdens black voters and those who lean Democratic.
The state argues that scrapping the days helped alleviate administrative burdens for local elections officials while reducing costs and the potential of fraud.
More than 60,000 people voted during golden week in 2008, while over 80,000 cast ballots during the period in 2012, according to court filings.
A federal appeals court is set to decide on a challenge to two laws that could affect how absentee or provisional ballots get cast and counted in the state.
The laws require voters to provide certain identifying information when casting such ballots and cuts the time voters have to fix any problems with them.
Under the 2014 laws, voters must accurately provide their names, addresses, birthdates, signatures and forms of ID when casting absentee or provisional ballots, otherwise they risk their votes not being counted.
One federal judge has upheld the laws, while another has ruled them unconstitutional.
Advocates for the homeless and the Ohio Democratic Party sued the state's Republican elections chief over the laws. They claim the ballot rules create new hurdles for voters, particularly minorities, in violation of their constitutional rights.
The state's attorneys argue the laws being challenged are nondiscriminatory, impose a minimal burden on voters and help elections officials more easily identify voters and update registration information.
A separate lawsuit pending in federal appeals court challenges how Ohio maintains its voter rolls.
Groups including the American Civil Liberties Union of Ohio and the New York-based public advocacy group Demos sued Republican Secretary of State Jon Husted over the process.
The groups claim Ohio illegally removes eligible voters based on their failure to vote in recent elections.
The state has used this so-called supplemental process for more than 20 years, according to Husted. He says Ohio fully complies with state and federal laws.
The lawsuit accuses Husted of canceling registrations in part because of voters' failure to respond to a notice mailed to their registered address. In Democrat-leaning Cuyahoga County, home to Cleveland, about 40,000 individuals were tossed from voter rolls in 2015 for choosing not to vote, with a disproportionate number from poor and minority neighborhoods, according to the Ohio chapter of the A. Philip Randolph Institute, a labor group representing minorities.
A federal judge rejected the lawsuit in June, saying Ohio's procedures ensure the integrity of its election process.
The groups want Husted to restore to the rolls eligible voters who they say have been unlawfully dropped or, alternatively, to count the provisional ballots those voters cast.