Former President Donald Trump has endorsed JD Vance in the crowded Ohio Republican Senate primary. CNN Political Director David Chalian explains how Vance went from a Trump critic to a Trump fan, and how Trump justified Vance’s past comments. This race will be one of many primaries in May where Trump’s party influence will be put to the test. Even if Trump’s candidates don’t win, some other candidates have aligned themselves with him – so what would that mean for the future of the GOP?To learn more about how CNN protects listener privacy, visit cnn.com/privacy