At 7 p.m. on Friday, the longest day of the year, the golden-hour light spilled over a block-long line of people outside of an indie bookstore in Manhattan’s East Village. It was the kind of queue typically reserved for Instagrammable pop-ups, the opening of a Stussy store, or a celebrity meet-and-greet. “Is he in there?” a few pedestrians murmured, craning their necks towards the storefront.
The “he” in question was 33-year-old New York City mayoral candidate Zohran Mamdani. And to…