Eligible adults who missed the voter registration deadline before the primary election can sign up before the Nov. 7 general election, in which winning candidates from each political party will face off against each other.

And if past trends continue, Hawai'i's voter rolls will swell with thousands of additional names before the Oct. 9 registration deadline.

"What is normally seen between the primary and general elections is that voters are activated and excited by the contests and the candidates," said state voter services coordinator Rex Quidilla. "There's also a sense that the general election has a certain finality to it. It is an election where the winners are determined."

More than 650,000 voters are registered, but only about 4 out of every 10 actually voted in the Sept. 23 primary. That's a dismal rate, but a higher turnout than for any Hawai'i primary since 1998, state election records show.

Voter turnout traditionally increases for general elections, but how much it will rise this year is anyone's guess. Some races were clearly decided in the primary, with only token opposition remaining. Others are expected to be hard-fought battles, especially for some state House seats.

Voter turnout in the 2004 general election, which included a presidential race, shot up by 20,000 more votes than that year's primary. But turnout in the 2002 general increased by less than 10,000 over the primary.

Voters must re-register if they have moved or changed their name. Registered voters unable to get to the polls on election day can apply to vote early, by requesting a mail-in ballot by Oct. 31 or visiting a walk-in poll site from Oct. 24 to Nov. 4.

Reach Johnny Brannon at jbrannon@honoluluadvertiser.com.