WASHINGTON – At the shorthanded U.S. Supreme Court, the next deadlock may affect the November election.

A group of voting rights cases is making its way to a court that's all but guaranteed to have a lingering vacancy through the election. The divisive nature of the issues may leave the eight justices unable to decide who can cast the ballots that will determine control of the White House and Congress.

The disputes involve voter identification requirements in Texas, Virginia and Wisconsin; an early-voting period in Ohio; a variety of restrictions in North Carolina; and proof-of-citizenship laws elsewhere. The cases pit Democrats and civil rights groups claiming discrimination against Republicans arguing that the steps are warranted to prevent voter fraud.

"They affect the rights of voters to be able to cast an effective ballot that will be counted accurately," said Rick Hasen, an election law professor at the University of California, Irvine.

The eight-member court deadlocked in four cases in its just-completed term. Justice Antonin Scalia died in February, and Senate Republicans have refused to consider President Obama's nomination of Judge Merrick Garland to fill the slot.

The vacancy increases the potential for the cases to produce varied outcomes from state to state. A 4-4 Supreme Court split leaves the lower court ruling in place.

The first case to arrive is likely to be the Texas voter ID fight. A federal trial judge found that more than 600,000 Texans, including a disproportionate number of blacks and Hispanics, lacked one of the required forms of identification. The measure lets voters use driver's licenses, military IDs and concealed-handgun permits, but not student or employee IDs. Texas officials say those challenging the law haven't pointed to any specific person who is unable to obtain an accepted form of identification.

The Supreme Court in April effectively gave the lower court a deadline, saying it would be willing to revisit blocking the law if the appeals court hadn't acted by July 20.

A different federal appeals court is taking an expedited look at North Carolina's voting rules, which include a photo ID requirement, the elimination of same-day registration and a reduction in the days available for early voting. Other cases aren't as far along but still could reach the high court on an emergency basis.