(Washington Times) President Obama’s health care law may have been ruled constitutional last year, but it now faces a legal challenge over whether the federal government can pay out subsidies in states that have refused to set up their own insurance exchanges.

Congressional Republicans and Oklahoma’s attorney general say only states that have set up their own virtual insurance markets, or “exchanges,” are eligible for the tax credits to help individuals buy insurance. The Obama administration disagrees.

The fight could be worth $500 billion — the value of tax credits that would be paid over the next decade to 25 states that have refused to run their own exchanges and instead say they will let the federal government take control, according to House oversight committee staff.

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