Mamdani’s mother, Mira Nair, is an award-winning filmmaker whose credits include “Monsoon Wedding,” “The Namesake” and “Mississippi Masala.” His father, Mahmood Mamdani, is an anthropology professor at Columbia University.

Mr. Mamdani would be the first Muslim mayor of New York City, and his faith played a role in expanding the diverse coalition that propelled his campaign.

For Muslim Americans across the country, his victory was a historic moment — one that cast a sharp rebuke toward Islamophobia.