Washington (CNN) If the Supreme Court decides against the Obama administration over subsidies that help cover health insurance costs at the heart of Obamacare, House Republicans are hatching a plan that would almost immediately reintroduce those same subsidies.

That means the same House GOP conference that has voted more than 50 times to repeal all or parts of Obamacare would be ready to offer a short-term transition period to keep those stripped of a subsidy afloat as they search for health insurance.

The move is likely an attempt to blunt any political fallout that could come if millions of people lose their ability to pay for health insurance, something Democrats would be sure to pin on Republicans.

But even if the GOP-led House and Senate pass this legislation, President Barack Obama has already pledged to veto any bill that rolls back all or significant parts of his signature health care law, as the Republican plan would eventually do.

The Supreme Court could rule in the case -- Burwell vs. King -- as soon as Thursday.

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