Most people (53 percent) now disapprove of Obamacare, compared with 41 percent who approve. Indeed, just a week before the deadline to buy health insurance on the Obamacare exchanges, opposition to the law is as high as the annual cap on out-of-pocket expenses for a family plan at the Bronze level.

The bigger problem? Many uninsured people have no idea what that last sentence means.

For a new study released today in the Proceedings of the National Academy of Sciences, researchers asked 3,414 Americans a battery of questions about Obamacare. Since most people get health insurance through work, they also targeted a sub-set that could stand to benefit from the law: people who are eligible for Medicaid, the uninsured, or those who make between 100 and 400 percent of the poverty level and thus qualify for the subsidies to buy health insurance.

The results were bleak—just two-thirds of the overall respondents knew that they had to get health insurance this month or face a penalty. Just over half knew about the exchanges to buy health insurance through Healthcare.gov, and less than half knew there might be subsidies available to help them afford coverage.

PNAS

And less than a third knew about the finer points of the law, like the fact that plans must now offer certain required benefits or that people cannot be denied coverage because of pre-existing conditions.