Tuesday is Election Day, and most Mainers who exercise their right to vote will likely get a bonus gift: no long waiting lines.

Statewide voter turnout is expected to be light on Election Day, although polling places are likely to be busier in Portland and other communities with municipal races on the local ballot, according to Maine’s top election official.

In Portland, voters will choose their mayor in the state’s only ranked-choice municipal election. There also are mayoral elections in Biddeford, Saco, Westbrook, Lewiston and Auburn, as well as other municipal and school board races in those and many other communities.

Some cities and towns will also have important referendum questions on their ballots. South Portlanders will vote on a new middle school and Scarborough voters will decide on a land conservation measure, to name two examples.

Secretary of State Matt Dunlap said he anticipates a 10 to 20 percent voter turnout statewide on Tuesday, while some local communities expect turnouts around 25 or 30 percent. That’s not unusual compared to other off-year elections with no controversial state ballot questions, but it’s a sharp drop from a presidential election when Maine’s turnout can exceed 70 percent.

This year, the state ballot includes only a transportation bond and a constitutional amendment, which “don’t tend to generate as much smoke and fire as candidate elections,” Dunlap said.

“What will drive most of the turnout is local elections,” he said. “You have the mayoral race in Portland, which is a pretty vivid take. I think people will be out in force for that.”

Dunlap said he is urging people “to not take a pass” on this election.

“There’s no such thing as a small election,” he said. “It’s a bond question and a constitutional amendment, but these are important things.”

The state bond question asks for voter approval to borrow $105 million for the state’s transportation infrastructure. The proposal includes $80 million for road and bridge construction, $20 million for ports, harbors, airports, railroads, public transit and bicycle and pedestrian trails, $1 million to improve the pier at Maine Maritime Academy in Castine, and $5 million to upgrade municipal culverts.

Mainers have overwhelmingly supported the last four transportation bonds with at least 59 percent of the vote, although there are concerns that regular borrowing for such projects masks persistent budget shortfalls to maintain and upgrade the state’s battered highway infrastructure. The $105 million requested in this ballot question will end up costing taxpayers $135 million over the 10-year life of the bond.

The other question on the state ballot would change the Maine Constitution to make it easier for people with disabilities to take part in citizen petition drives. If passed, voters who have physical disabilities would be allowed to use an alternative method of signing a petition, such as using a signature stamp or authorizing another Maine-registered voter to sign on the their  behalf.

The mayor’s race has attracted the most attention in Portland, with Mayor Ethan Strimling being challenged by City Councilor Spencer Thobodeau, former school board member Kate Snyder and political newcomer Travis Curran.

The four way race is widely expected to be decided in a ranked-choice “runoff.” If none of the four candidates gets more than 50 percent of the vote in the first count, the last-place candidate is eliminated and his or her votes redistributed based on who was designated as each voter’s second choice. That process can repeat until one candidate gets more than 50 percent of the votes.

Polls open Tuesday morning across the state. Voting begins at various times depending on the community, but polls open at 7 or 8 a.m. in the vast majority of cities and towns. All Maine polls will close at 8 p.m.

Maine residents 18 and older can still register to vote, even on Election Day.

According to the secretary of state, 25,008 absentee ballots were requested and 13,289 had been returned as of Oct. 28.

In Portland, the contentious mayoral race is likely to drive voters to the polls.

City Clerk Katherine Jones said about 3,200 Portland voters requested absentee ballots and about 2,100 were returned as of Friday. That’s about the same level of absentee voting as the last mayoral race in 2015.

Jones said she expects a similar overall voter turnout to 2015, when 19,000 voters cast ballots, about 32 percent of all registered voters.

In Biddeford, residents will elect a mayor, as well as nine city councilors and seven school committee members. City Clerk Carmen Morris had issued 1,364 absentee ballots by Thursday afternoon and received back just over 1,000 ballots.

Morris said that number of absentee ballots is about average for a municipal election in the city, but she believes overall voter turnout in Biddeford will be slightly higher than the statewide turnout for this election.