AUGUSTA (AP) – A challenge has been filed in an attempt to keep independent U.S. Senate candidate Herbert Hoffman’s name off the November ballot, Maine election officials said Friday.

John Knutson of Brooklin, chairman of the Maine Democratic Party, claims that a number of voters’ signatures on petitions to get Hoffman’s name on the ballot are invalid. The Secretary of State’s Office has scheduled a hearing Monday for Knutson to present evidence of his claims.

Knutson’s challenge was submitted after election officials determined that Hoffman’s petitions contained 4,112 valid voters’ signatures, 112 more than the 4,000 required by state law. Hoffman, from Ogunquit, is a former Democrat.

State Democratic Party officials are worried that Hoffman’s appearance on the ballot could draw votes away from the party’s nominee for Senate, Rep. Tom Allen. The votes could be crucial to Allen’s chances of beating incumbent Republican Sen. Susan Collins.

The Secretary of State’s Office has also determined that another independent, Laurie Dobson of Kennebunkport, failed to submit enough signatures to get on the ballot by the late-May deadline. Officials said Dobson was 160 signatures short of the minimum.

On June 3, Dobson requested extra time to submit additional signatures, but election officials denied her request, saying it did not have the legal authority to do so.

AP-ES-06-13-08 1449EDT