Washington (CNN) -- Obamacare -- the law that refuses to die -- is suddenly under attack again. Republicans will take full control of Congress in January and repealing Obamacare will almost certainly be one of their first priorities. The GOP is seizing on leaked tapes in which MIT professor Jonathan Gruber, an architect of the law, said the "stupidity of the American voter" and a "lack of transparency" were vital to its passage in 2010. And, perhaps most importantly, the Supreme Court is poised to rule on subsidies that are central to the law. "We have to take it very seriously. It is hard to predict how the Court will ultimately decide," said Ron Pollack, executive director of Families USA, an advocacy group that campaigns to sustain Obamacare.
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New challenges have arrived for President Barack Obama's top domestic achievement
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Supreme Court again holds law's fate in its hands
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Republicans will struggle to 'repeal and replace'
The law has already survived one key @placeholder challenge and millions are now insured because of the legislation.