Gov. Scott Walker (Wis.), a Republican who has been one of ObamaCare’s most vocal opponents, signed a bill Tuesday that would shore up the law’s insurance markets.

The bill would authorize the state to apply for a federal waiver to offer a reinsurance program covering 80 percent of medical claims costing between $50,000 and $250,000.

The program would cost $200 million, with the federal government paying 75 percent of the costs, and is meant to lower premiums for everyone else by paying for claims filed by the sickest, most expensive patients.

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