CLEVELAND — Thousands of people who are registered voters in Ohio and Florida possibly could vote twice in the presidential election through use of absentee ballots, The Plain Dealer reported Sunday. An investigation of voter rolls in the two key battleground states found that some double voting has occurred previously and could go undetected Tuesday, the newspaper said. Many states have only just begun to compile statewide voter registration lists to comply with a 2002 federal voting law. Such lists allow state officials to find double registrations within a state, but states rarely coordinate with one another. Virtually nothing prevents...