Voters in pivotal Ohio with outdated addresses face possible pre-election challenges and trips to multiple polling places. They also are more likely to cast provisional ballots that might not be counted.
"It's a real issue," said Daniel Tokaji, an Ohio State University law professor who specializes in elections. He wonders whether foreclosures might explain the increasing percentages of provisional votes cast between 2004 and Ohio's latest election, the presidential primary in March.
Ohio provided President Bush with an 118,000-vote victory in 2004, giving him the electoral votes he needed to win the election.
Nearly 3,700 people are registered to vote at Columbus addresses the city lists as vacant, according to records maintained by the city's code-enforcement office and the Franklin County Board of Elections, The Columbus Dispatch reported.
The number of voters on the move is higher than that. The Franklin County Board of Elections sent notices in January to about 27,000 residents who had filled out change-of-address forms but failed to update their voter registrations.
Only about 10,000 had responded through the end of May, but deputy elections director Matthew Damschroder said that partly accounted for a 25 percent increase in new registrations and address changes compared with 2004.
Voters - not the county - are responsible for keeping registrations current. Boards of health send regular updates so they can remove dead people from the rolls.
In Franklin County, people who are alive and registered but don't vote are removed after sitting out eight years of elections.
Ohio's requirement that voters show identification at the polls makes it more important that they keep their registration information current, said Jeff Ortega, a spokesman for Secretary of State Jennifer Brunner, Ohio's elections chief.
In 2004, the Ohio Republican Party challenged more than 31,000 newly registered voters statewide after letters it mailed out came back as undeliverable. The challenges failed, but Brunner said a new state law requiring counties to mail their own notices to all registered voters could lead to another round of pre-election challenges.
Columbus ranked 32nd among U.S. cities in the number of foreclosure filings during the first quarter of 2008, according to RealtyTrac, a Web site that lists homes on the market in most cities. Cleveland, Dayton, Akron, Toledo and Cincinnati also were among the top 50, and Ohio was ninth among states during May, with one filing for every 410 homes.
Other battleground states rank high in foreclosure filings as well: Nevada led the nation in May with one filing for every 118 homes, while Florida was fourth, Michigan fifth, Georgia sixth, Colorado seventh and New Jersey 10th.
Franklin County GOP Chairman Doug Preisse didn't rule out challenges before Nov. 4. He said his party wants "clean, accurate voter lists."
As it did in 2004, the Ohio Democratic Party is putting together a "voter-protection" plan to fight eligibility challenges.