COLUMBUS, Ohio: The Ohio Supreme Court and a federal judge yesterday upheld a weeklong period in which new voters can register and cast an absentee ballot on the same day in Ohio, a blow to Republicans in a partisan battle.

Ohio is a battleground state where Republican President George W. Bush narrowly clinched re-election in 2004 .

In a 4-3 decision, the Ohio Supreme Court said Secretary of State Jennifer Brunner was correct in ruling that voters do not need to be registered for at least 30 days before receiving an absentee ballot. Brunner, a Democrat, has been criticized by Republicans who have said she interpreted the same-day registration and voting window to benefit her own party.

Democratic presidential candidate Barack Obama’s campaign has extensive plans to get college students around the state to register and vote during the window.

Other groups, including the Northeast Ohio Coalition for the Homeless, have plans to drive the homeless, low-income and minority voters to the polls during the window. Such voters tend to vote Democratic.

Republicans have said they were concerned that providing an absentee ballot to a voter before checking whether the registration was valid would open the door to voter fraud.

Another federal court decision was expected later in the day over the early voting window, which begins today.

Although both Obama’s campaign and the Republican National Committee have urged supporters in Ohio to use the early voting, Republican-backed lawsuits were filed against it. Earlier yesterday, US District Judge James Gwin in Cleveland issued a temporary restraining order forcing Madison County to follow Brunner’s instructions.

The county had said that on the advice of its county prosecutor it was not going to allow same-day voting during the six-day window that runs through Oct. 6. The Ohio Supreme Court has six Republicans and one Democrat. Gwin was appointed to the bench by former President Bill Clinton.

In the day’s last courtroom battle, the Ohio Republican Party has filed a statewide challenge in federal court in Columbus before a judge appointed by former President Ronald Reagan.

The ruling by the Ohio Supreme Court was loss for two voters who had sued and were backed by the state Republican Party.

Republicans argue that Ohio law requires voters to be registered for at least 30 days before they cast an absentee ballot and that the law doesn’t allow same-day registration and voting.

But Brunner interpreted the law correctly, Gwin said in his ruling.