[3] Among the seat's prior occupants are former Mayor Bill de Blasio and current Comptroller Brad Lander.

District 39 is based in the Brooklyn neighborhood of Park Slope, also stretching west and south to cover Gowanus, Cobble Hill, Carroll Gardens, Columbia Waterfront, and parts of Windsor Terrace, Borough Park, and Kensington.

[6] In 2019, voters in New York City approved Ballot Question 1, which implemented ranked-choice voting in all local elections.

Under the new system, voters have the option to rank up to five candidates for every local office.

If one candidate surpasses 50 percent in first-choice votes, then ranked-choice tabulations will not occur.