Voting in Saturday's Democratic primary election in Hawaii has been postponed in two precincts because of Tropical Storm Iselle, officials said Friday.

"There's been such serious damage unfortunately [and] there have been all kinds of road closures," state Attorney General David Louie told local ABC affiliate KITV4.

Downed trees in the vicinity of the polling centers rendered the sites accessible to would-be voters. "We got civil defense reports that show there are miles of roads that have albizia trees" blocking them, Louie said.

Both precincts are on the Big Island. Nearly 3,900 residents cast ballots in them in 2012, according to KITV4. Voters wishing to cast ballots there will now have to vote absentee.

The rest of the election is proceeding as planned. Iselle made landfall Friday on the Big Island.

Saturday's Democratic primary is the biggest in a generation in the Aloha State. Sen. Brian Schatz is trying to hold his seat against Rep. Colleen Hanabusa. The two Democrats competed in an intense and deeply personal campaign.

Meanwhile, Gov. Neil Abercrombie (D) is in danger of becoming the first governor to be unseated this year. He faces state Sen. David Ige.