The proposal is an attempt to seize momentum on one of the campaign’s top issues — the housing crisis — and could affect nearly one million homes, or about 40 percent of the city’s rental market.

It’s also part of a continuing attack on the front-runner in the race, Assemblyman Zohran Mamdani, who pays $2,300 a month for a rent-stabilized one-bedroom apartment in Astoria, Queens.