HONOLULU — More than a third of the 317,337 ballots mailed to voters in the special election for Hawaii's vacant congressional seat have been returned.

State Office of Elections spokesman Rex Quidilla said Wednesday that an estimated 110,000 ballots have been received, almost 35 percent of those sent out.

The all-mail election will determine who represents the 1st Congressional District for the remainder of the current term, which ends in January.

Ballots are due at the Office of Elections or the state Capitol by 6 p.m. on May 22.

Results are expected to be released soon after 6 p.m. that day.