WASHINGTON (AP) — House Democratic Leader Nancy Pelosi says Republicans will "rue the day" if the Supreme Court buys their arguments and invalidates tax subsidies for millions of people under President Barack Obama's health care law.

Republicans have said they will try to ensure people don't lose coverage if the high court rules this summer against tax subsidies for health care coverage in certain states. But they haven't said how they would do it.

Such a ruling would present a major challenge to the GOP. An estimated 8 or 9 million people would lose subsidies, which lower their coverage costs.

Pelosi says such an outcome would be very bad for Republicans, although she also insists that the health law is ironclad unconstitutionally and will stand up in court.