Polls opened at 7 a.m. across the city, with two races on the ballot in Dorchester's District 3: Two men are vying to succeed retiring City Councillor Maureen Feeney and seven-person field is fighting for the four City Council At-Large slots.

The two top finishers in the Sept. preliminary, Frank Baker of Savin Hill and John O’Toole of Cedar Grove, are facing off over the first open City Council seat in Dorchester in nearly 18 years.

The polls close at 8 p.m.

In the at-large race, the four incumbents -- Stephen Murphy, John Connolly, Felix Arroyo and Ayanna Pressley -- are running for reelection. Former City Councillor Michael Flaherty, Hyde Park activist Will Dorcena and past City Council candidate Sean Ryan are also running. At-large councillors represent the entire city.

There are also contested races in Districts 2, 4 and 7. In District 2, former school principal Suzanne Lee is challenging incumbent Bill Linehan, while in District 7, incumbent Tito Jackson, who won a special election in March, is facing Fenway’s Sheneal Parker. In District 4, longtime incumbent Charles Yancey will battle frequent opponent J.R. Rucker.

District 3 includes Ward 1 Precinct 15; Ward 13 Precincts 3 & 6-10; Ward 15 Precincts 1, 3, 4 & 6-9; Ward 16 Precincts 1-12; and Ward 17 Precincts 4 & 12-14.

Polling locations can be found here: http://www.cityofboston.gov/elections/voter/

The O’Toole camp’s election night party is set for the McKeon Post, while the Baker team is holding their party down the street at Florian Hall.

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