It’s hard to recall a midterm primary season as unsettled and unpredictable as the one ahead. In 2025, of course, President Donald Trump triggered a House redistricting arms race in Texas, which was quickly answered by California’s Gavin Newsom—redrawing old district lines and potentially ending long congressional careers on both sides of the aisle. Democratic leaders are balancing their anticipation of a blue wave against early signals of an emerging Tea Party–style movement on the left, as activists agitate for primary challengers to knock off members of the establishment. Meanwhile, Republican leadership is bracing for a reckoning of its own, as Trump’s deteriorating approval ratings push once-solidly-red districts into tossup territory.