The Republican Party posted thousands of people inside Ohio (search) polling places to challenge voters' eligibility Tuesday after a dispute that went all the way to the U.S. Supreme Court just hours before the balloting began.

Republicans said they wanted challengers in precincts because of concerns about fraud, but Democrats filed lawsuits accusing the GOP of trying to suppress turnout and intimidate black voters.

But a three-judge panel of the 6th U.S. Circuit Court of Appeals (search) overturned the orders of two federal judges and ruled 2-1 early Tuesday that the presence of challengers was permitted under state law. The U.S. Supreme Court declined to step in.

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Both parties took advantage of the ruling, but there were only a few reports of challengers disputing people's registrations.

"It's just not turning out to be as large of an issue as it could have possibly been," said Molly Lombardi, spokeswoman for the Election Protection Coalition, one of several groups monitoring the voting.

Some GOP challengers compared the names of people voting with lists of absentee voters and people who died recently. Others from both parties helped direct voters to their correct precinct if they were in the wrong ones.

"Things seem to be going smoothly," Democratic party spokesman Myron Marlin said.

About 90 percent of the 3,500 challengers registered by Republicans showed up to work the polling places, said Mark Weaver, a lawyer for the Ohio GOP. Democrats say they have thousands of challengers but will not give a specific number.

Hundreds of thousands of new voters have signed up this year in a state President Bush (search) and Sen. John Kerry (search) both need to win.

Under state law, voters may be challenged on their citizenship, age or residency. Poll workers generally would challenge someone if his or her signature did not match the one in the poll book, or if the poll worker recognized the individual as someone who did not belong in that precinct.

In a separate ruling, a federal judge ruled Tuesday that Ohio voters who did not receive absentee ballots on time can cast provisional ballots at the polls. Provisional ballots are essentially backup ballots given to voters who find they are not listed on the rolls. It was unclear how many voters were affected by the ruling, which reverses an earlier directive by Republican Secretary of State J. Kenneth Blackwell.

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