"Of the 23 million people who either buy health insurance through the marketplaces set up by the law (roughly 11 million) or receive coverage through the expansion of Medicaid (12 million), about 21 million are at serious risk of becoming uninsured if Obamacare is struck down. That includes more than nine million who receive federal subsidies. On average, the subsidies cover $492 of a $576 monthly premium this year, according to a report from the Department of Health and Human Services. If the marketplaces and subsidies go away, a comprehensive health plan would become unaffordable for most of those people and many of them would become uninsured.
Medicaid, the government insurance program for the poor that is jointly funded by the federal government and the states, has been the workhorse of Obamacare. If the health law were struck down, more than 12 million low-income adultswho have gained Medicaid coverage through the law’s expansion of the program could lose it."