The first duty of local election officials is to inform citizens when and where they may vote. A simple task, it would seem, but one also vulnerable to hard-to-explain error. It has happened at least a couple of times in the last week, and while the numbers involved are small, they run the risk of adding up to something in an election as tight as this one.

On Friday, officials in Ottawa County, Ohio discovered that about 2,200 notices had gone out announcing Election Day as Thursday, Nov. 8 (instead of Tuesday, Nov. 6). They also got a polling place location wrong. (The county board's website does not list the election date.)Elections director JoAnn Friar said Monday that the problem involved just three precincts and that they would be sending out corrected notices soon. Asked what happened, Friar, a Republican, attributed the glitch to computer error.

Ottawa County, on Lake Erie in northeast Ohio near Toledo, has about 30,000 registered voters and swings just like the state. It went for Obama in 2008 with 52 percent of the vote and for George W. Bush in 2004, 50-48 over John Kerry.

They're having calendar challenges in Arizona as well. Maricopa County said it listed the election as Nov. 8 in about 50 voter registration cards printed in Spanish. Officials called it an honest mistake.