US Supreme Court Justice John Paul Stevens today allowed Republicans to challenge voter qualifications at the polls in Ohio, a key battleground state that could determine the presidential election.
Justice Stevens acted on an emergency request shortly before polls opened in Ohio and across the nation. He refused to set aside a US appeals court order that allowed political parties to send challengers to polling places across the state.
Republicans have been planning to make major use of the challengers in what they call an effort combat voter fraud, while Democrats have accused their rival party of attempting to intimidate voters.
The appeals court had reversed the ruling of two federal judges in Ohio who ordered the challengers to stay out of the polling places or to remain only as witnesses.
Ohio, a focal point in the election, is seen pivotal to the electoral fortunes of both US President George W. Bush and his Democratic challenger, Senator John Kerry. No Republican has ever won the White House without carrying Ohio, and polls show Mr Bush and Mr Kerry in a tight battle for the state.
Ohio is one of several states where the parties have prepared for potential legal challenges of the results, which could delay the outcome of a close election. A five-week recount battle in Florida in 2000 was ultimately resolved by the Supreme Court, which handed Bush the presidency.
Justice Stevens said practical considerations, such as the difficulty of reviewing all of the relevant filings in the two cases and the limited amount of time available, weighed against granting the requested relief and reinstating the orders of the federal judges.
"The hour is late and time is short," said Justice Stevens, who refused to refer the matter to the full Supreme Court.
The lawsuits claim that Ohio Republicans plan to send hundreds of challengers into predominately African-American neighborhoods to mount indiscriminate challenges at polling places, causing voter intimidation and delays in voting.