The survey found that 56 percent said they knew "nothing at all" about the high court challenge, which targets subsidies issued to most customers of HealthCare.gov. The federal health insurance marketplace serves 37 states, and so far this year has seen sign-ups by more than 6 million people who qualify for subsidies.
Just 14 percent of respondents said they knew "some" or "a lot" about the case targeting the aid, which is available to Obamacare customers with low or moderate incomes.
But 64 percent agreed that "Congress should pass a law" to restore the HealthCare.gov subsidies if the Supreme Court said the ACA as written does not allow them. While Democrats and self-described independents were the most supportive of that view, 40 percent of Republican respondents said Congress should pass a remedy.
In states served by HealthCare.gov, 59 percent said they would want their state to create its own Obamacare exchange in the face of a high court decision ruling the federal exchange subsidies are illegal. And a slight majority of Republicans in those states, 51 percent, agreed that their state should take such action.
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The vast majority of people who buy Obamacare plans on government-run exchanges qualify for tax credits to help them pay their monthly insurance premiums. If those subsidies are not available, there is widespread agreement among insurance experts that enrollment in Obamacare plans would plummet because many people would find their retail prices unaffordable.
In the pending court case, plaintiffs argue that the ACA allows the subsidies to be issued only to customers of one of the 14 insurance exchanges established by individual states and the District of Columbia. Plaintiffs say the aid is not an option for HealthCare.gov customers because the ACA only explicitly authorizes subsidies to customers of an exchange established by a "state."
The Obama administration disputes that, and has said it is confident the subsidies will continue for HealthCare.gov customers.
The Supreme Court is due to hear arguments March 4, and is likely to rule in June.