Ella Emhoff, the stepdaughter of failed presidential candidate Kamala Harris, officially backed Democratic socialist candidate Zohran Mamdani for New York City mayor on Sunday ahead of his rally at Brooklyn Steel.

Throngs of demonstrators marched through the normally sleepy streets of Sheepshead Bay to protest plans for a family homeless shelter — as locals claimed the city pulled a bait and switch to get the project OK’d. A long caravan of cars snaked through about 20 blocks of the Brooklyn neighborhood Sunday while crowds carried signs...