New York's congressional candidates spent Monday making closing arguments ahead of Tuesday's primary elections — and the story is simple: incumbents are running scared. Mayor Zohran Mamdani has endorsed a trio of progressive challengers, including community organizer Darializa Avila Chevalier taking on Rep. Adriano Espaillat in upper Manhattan and the Bronx, and Assemblymember Claire Valdez vying for Rep. Nydia Velazquez's open Brooklyn seat against...