Franklin County's unofficial results had Bush receiving 4,258 votes to Democrat John Kerry's 260 votes in a precinct in Gahanna. Records show only 638 voters cast ballots in that precinct. Bush's total should have been recorded as 365.

Bush won the state by more than 136,000 votes, according to unofficial results, and Kerry conceded the election on Wednesday after saying that 155,000 provisional ballots yet to be counted in Ohio would not change the result.

Deducting the erroneous Bush votes from his total could not change the election's outcome, and there were no signs of other errors in Ohio's electronic machines, said Carlo LoParo, spokesman for Ohio Secretary of State Kenneth Blackwell.

Franklin is the only Ohio county to use Danaher Controls Inc.'s ELECTronic 1242, an older-style touch-screen voting system. A message seeking comment was left Friday for Danaher.

Sean Greene, research director with the nonpartisan Election Reform Information Project, said that while the glitch appeared minor, "that could change if more of these stories start coming out."

In one North Carolina county, more than 4,500 votes were lost Tuesday because officials mistakenly thought a computer that stored ballots electronically could hold more data than it did.

And in San Francisco, a malfunction with custom voting software could delay efforts to declare the winners of four races for county supervisor.

In the Ohio precinct in question, the votes are recorded to eight memory locations, including a removable cartridge, according to Verified Voting Foundation, an e-voting watchdog group. After voting ends, the cartridge is either transported to a tabulation facility or its data sent via modem.

Kimball Brace, president of the consulting firm Election Data Services, said it's possible the fault lies with the software that tallies the votes from individual cartridges rather than the machines or the cartridges themselves.

County officials did not return calls seeking details.

Matthew Damschroder, director of the Franklin County Board of Elections, told the Columbus Dispatch that on one of the three machines at that precinct, a malfunction occurred when its cartridge was plugged into a reader and generated a faulty number. He could not explain how the malfunction occurred.

Damschroder said people who had seen poll results on the election board's Web site called. The error would have been discovered when the official count for the election is performed later this month, he said.

The reader also recorded zero votes in a county commissioner race on the machine.

Other electronic machines used in Ohio do not use the type of computer cartridge involved in the error, state officials say.

A batch of accidentally double-counted ballots in a punch-card system in southeast Ohio's Perry County resulted in about 75 more votes than there are voters in one precinct, county Elections Director Janie Dailey said. Workers tried to cancel the count when the tabulator broke down midway through, but the machine instead double-counted the first batch. The mistake will be corrected during the official count beginning Nov. 16, and the number of ballots that were counted twice will not be known until then, she said.