Shortly before New York’s new mayor, Zohran Mamdani, delivered his rousing victory speech to a packed hall in Brooklyn on Tuesday night, one person was singled out for praise: Elle Bisgaard-Church, his 34-year-old chief adviser… It was a fleeting moment in the spotlight for Bisgaard-Church…She rarely speaks in public or gives interviews and, unusually for a New York politico, does not post on X. Yet she has masterminded one of the most improbable, closely-watched and successful campaigns in recent political history, propelling an obscure socialist candidate to the highest office of the most important city in the US. Patrick Gaspard,...