It's a mayoral race that no one could have predicted at the beginning of the year, and one that will leave Seattle watching and wondering until the very end.

“I think it's anybody's guess right now,” said one Seattle voter named John dropping off his ballot Monday.

“It’s been something that has been a part of the news cycle it feels like six, seven months, kinda been thinking about it for that long,” said another Seattle voter named Zach who declined to give his last name.

After a whirlwind year in city politics and the unexpected resignation of former Mayor Ed Murray, Tuesday’s election will bring a new chapter at Seattle City Hall and will produce the city's first female mayor in 91 years—either former U.S. Attorney Jenny Durkan or urban planner Cary Moon.

“I think it's going to be very close,” said John.

With a large number of ballots not yet turned in, both candidates spent their final campaign weekend working to win over undecided voters and canvassing in the cold.

Durkan held her last neighborhood tours; Moon held a Facebook live to answer last minute questions.

Moon believes she may have an edge with younger voters, like Zach who dropped off his ballot today.

“I think it's going to come down to the vision people have for the city,” he said.

Durkan supporters still cite experience as one of the top reasons they're drawn to her campaign.

“We need someone who knows how to run a big machine. I think she's going to be better at managing the situation, but we'd sure like to get Cary's ideas in there,” said Austin Watson.

“I really want Cary to work for Jenny,” he said.

Despite the high-profile race, voters appear to be hanging onto their ballots later than usual. Turnout in King County stood at around 20 percent heading into Election Day. The county is still expecting turnout to reach around 48 percent, according to a spokesperson.

Related: Find a drop box near you

Election workers are expecting a surge of ballots returned on Tuesday and delivered to dropbox locations until the deadline of 8 p.m. on election night.

“If I was to be honest, I had to really motivate myself to vote this time around,” said voter Emily McArthur, who supported Nikkita Oliver during the primary cycle.

“I think it was really exciting for everyone to have a break from business as usual politics,” she continued.

McArthur says she was far less enthusiastic to vote in the general, in a race that will highlight Seattle's different shades of blue.

“For me and people I care about, Cary Moon is the better choice. As an activist, we're still going to have to challenge her on a lot of the issues,” said McArthur.

“I think we kinda already had the activist mayor in McGinn, so I voted for Jenny Durkan this time,” countered Steve Stearns. “Being an activist is a different job than being a politician and actually building coalitions and bringing people together. I just see Durkan more able to do that than Moon.”

The first batch of results is expected to post just after 8 p.m. on Tuesday. KING 5 will be tracking all the big races including the mayoral races in Seattle, Everett and Tacoma, as well the Eastside senate race that will determine the balance of power in Olympia.

Other big local races on the ballot include the open race for Seattle City Council position 8, the Seattle City Attorney’s race and King County Sheriff’s race.