But Republicans vowed to fight on and quickly filed a similar lawsuit in the State Supreme Court.
The legal battle concerns as many as 200,000 of the 660,000 new voters who have registered in Ohio since Jan. 1, according to Social Security Administration and state election officials.
The United States Supreme Court, in a brief, unsigned decision, said lower federal courts in Ohio should not have ordered the secretary of state, Jennifer Brunner, to turn over the information. The court acted just before a deadline set by a federal judge in Columbus requiring Ms. Brunner to act.
A 2002 federal law, the Help America Vote Act, or HAVA, requires states to check voter registration applications against government databases like those for driver’s license records. Names that do not match are flagged. Ohio Republicans sought to require Ms. Brunner to provide information about mismatches to local officials.
Those officials could use information to require voters to cast provisional ballots rather than regular ones. They could also allow partisan poll workers to challenge people on the lists. Given the success by Democrats in registering new voters this year, those actions would probably affect that party’s supporters disproportionately.
The court said it expressed “no opinion on the question whether HAVA is being properly implemented.” But it said that Congress had probably not intended to allow private litigants like political parties to sue to enforce the part of the law concerning databases.
The decision also means that the Ohio Republican Party will not be able to make public-information requests to get the data so that poll workers can raise voter challenges.
Edward B. Foley, a law professor at Ohio State, said the Supreme Court’s action in letting state authorities handle matters in the face of a late challenge was consistent with a general premise of election law. “Federal court intervention is a last resort, even if it’s not at the last minute,” Professor Foley said.
Ms. Brunner welcomed Friday’s ruling.
“Our nation’s highest court has protected the voting rights of all Ohioans, allowing our bipartisan elections officials to continue preparing for a successful November election,” she said. “We filed this appeal to protect all Ohio voters from illegal challenges and barriers that unfairly silence the votes of some to the advantage of others.”
But the victory for Ms. Brunner might be short-lived.
Having lost before the United States Supreme Court, Republicans turned Friday to the Ohio Supreme Court.
David Myhal, a Republican from New Albany, filed a lawsuit asking the court to issue an order so that local election officials separate any ballots from voters whose registration information does not match records in state or federal databases.
The lawsuit seeks to require Ms. Brunner to order county elections boards not to count any absentee ballot from voters registered after Jan. 1 without first checking the statewide voter registration database to ensure there is no mismatch.
If there is a mismatch, the boards would be required to determine whether the person is an eligible voter.
The Ohio court gave Ms. Brunner until Monday to file her response, and said both parties must file briefs by next Friday.
Voting experts and state election officials have raised concerns about treating flagged voters differently because the databases used to check registrations are prone to errors. Most non-matches are the result of typographical errors by government officials, computer errors and use of nicknames or middle initials, not voter ineligibility, they said.
In one audit of match failures in 2004 by New York City election officials, more than 80 percent of the failures were found to have resulted from errors by government officials; most of the remaining failures were because of immaterial discrepancies between the two records.
Ms. Brunner has also argued that requiring so many voters to cast provisional ballots would raise tensions at the polls and worsen lines and confusion on an Election Day when she is expecting unprecedented turnout.
Republicans rejected those arguments.
“It remains our belief that American citizens should be guaranteed that their legitimate votes are not wiped away by illegally cast ballots,” said Rick Davis, the McCain-Palin campaign manager. “What is no longer in question is the partisan nature of Jennifer Brunner’s efforts to minimize the level of fairness and transparency in this election.”
Officials in the Ohio Republican Party had said they wanted the list so that local election officials could clear up any discrepancies before Election Day and in cases where that was not possible, those voters should use a provision ballot. Provisional ballots in Ohio are held for 10 days before being counted while workers check eligibility, and they are often subject to partisan wrangling and legal fights.
In 2004, President Bush won Ohio by about 118,000 votes. During that race, litigation over Republican plans to challenge about 35,000 voters went to Justice John Paul Stevens on the eve of the election. Justice Stevens said it was too close to the election to intervene, but he added that he expected both sides to act in good faith. The Republicans dropped plans for their challenges.
Polling in the state shows Senator Barack Obama, the Democratic presidential nominee, with a slight lead on his Republican challenger, Senator John McCain.