Land-use policy has gotten little attention in the mayor’s race, but political observers say it is an issue over which the mayor can exert significant influence. He or she appoints the majority of the City Planning Commission, including the chair. The mayor also established priorities for rezonings, which the City Planning Department carries out. Promoting high-density development can add to the tax base and shore up tight municipal budgets. The Bloomberg administration rezoned about 30% of the city, with a goal of transforming industrial areas like Hudson Yards, West Chelsea and the waterfront into hotbeds of luxury housing.

Mr. de Blasio has said he would shorten the timeline for debate on developments before they enter the formal approval process and promote more neighborhood-wide rezonings, as opposed to forcing developers to seek approval for large new projects individually. Mr. de Blasio, along with others, also supports so-called mandatory inclusionary zoning, requiring affordable units when areas are rezoned.

Some questioned whether including a smattering of affordable units in new luxury towers—which would likely still need some mix of government subsidies—is the best way to create a more equal city, as opposed to building affordable projects in low-income neighborhoods. “It’s not going to help central Brooklyn,” said Jerilyn Perine, executive director of Citizens Housing and Planning Council, a nonprofit group. “It’s not going to help the housing problems in the South Bronx.”