Republicans have tried to kill Obamacare more than 50 times. But the Supreme Court could actually do it with a single ruling.
Justices will hear arguments Wednesday on whether most Obamacare enrollees can keep their subsidies.
A ruling against the Obama administration could send Obamacare into a death spiral.
It's likely that millions of enrollees would drop coverage after losing their assistance, experts said. Insurers would stop offering coverage or be forced to hike rates - by more than 250% by one estimate. Many remaining customers could leave the market after their premiums soar.