Voters have been casting their votes since mid-October. And while early results will start trickling in Tuesday night, the final determination of who has won in some of the more competitive races likely won't be known for days, if not longer.
The race to replace Democratic Gov. Chris Gregoire is a tight contest between Republican Attorney General Rob McKenna and Democrat Jay Inslee, a former congressman.
Inslee and McKenna have raised more than $25 million combined during the campaign. In all, some $40 million has been spent on the race, including money shelled out by third-party groups on TV ads and mailers.
Polling has shown the gubernatorial contest is an extraordinarily close race. And with all but one of the counties doing just one vote-count release Tuesday night, it's likely no clear winner will emerge that evening.
"If it's close, it could be a while," said David Ammons, a spokesman for Secretary of State Sam Reed. Ammons said officials are expecting 90 percent of the vote will be counted by Friday.
Voters also will weigh in on statewide executive offices, seats in Congress and the Legislature, as well as the ballot measures on gay marriage, marijuana, charter schools and taxes.
At the top of the ticket, Democrat Barack Obama is favored to carry Washington's 12 electoral votes in his battle with Republican Mitt Romney for the White House.
Polls suggest U.S. Sen. Maria Cantwell will comfortably win re-election. Of the state's 10 congressional districts, the 1st District congressional race between Democrat Suzan DelBene and Republican John Koster is seen to be the most competitive.
Recent polling also shows support for Referendum 74, which asks voters to either approve or reject a gay marriage law passed by the Legislature this year. That law is on hold pending Tuesday's election.
Voters polled indicated support for another high-profile measure, regarding recreational marijuana use. Initiative 502 would legalize possession of up to an ounce of pot for those over age 21.
About 3.9 million are registered to vote in Washington, and Reed has predicted voter turnout will be at 81 percent, a bit lower than the state's record of 85 percent in 2008. The historic average is 79 percent.
At a large green and white ballot drop box in front of the King County administrative building in Seattle, a steady stream of people deposited their ballots Monday.
Under state law, ballots have to be postmarked by Election Day, but voters also have the option of dropping off ballots at local drop boxes. Reed has predicted that up to 60 percent of the expected vote will be counted by election night, leaving another 40 percent of ballots left to be counted, either en route by mail or left at the drop boxes counties have set up.
As of Monday afternoon, about 1.8 million ballots had been returned to the state's 39 county auditors.