Thousands of Mexicans gather at Zocalo Square in the capital for the closing campaign rally of ruling-party presidential candidate Claudia Sheinbaum. Mexico will hold a general election on June 2, and its next president will face an array of challenges, including managing migration, maintaining delicate relations with the neighboring United States, and addressing criminal violence that has left more than 450,000 people dead and tens of thousands missing since 2006. IMAGES