Mamdani-backed candidates swept New York's Democratic primaries, a win for the party's left wing and a worry for moderates and the right.

• Candidates Mamdani supported won their races, beating incumbents who usually have the advantage of staff, money, and donors.
• His pitch is bread-and-butter stuff: affordable housing, universal child care, better public transit, and worker protections.
• New York rolled out free child care for two-year-olds and signed heat-safety rules for outdoor workers.
• Fox News and right-wing voices are pushing back hard, framing his agenda as radical.
• The bigger point: policies like cheap health care, free transit for seniors, and tighter tech rules are normal in places like South Korea and much of the developed world.

Outlook: Expect more left-leaning, Mamdani-style candidates to keep challenging establishment Democrats heading into the next election cycle.