Yesterday I posted a chart from our graphics department, which showed who would fall through the cracks if a state opts out of the Medicaid expansion.

Aaron Carroll makes an important point about that chart: It only applies to parents. Childless adults tend to have even lower eligibility in state Medicaid programs. Forty-three states do not cover single adults at any level of the poverty line.

If those states opt out of the Medicaid expansion, adults without children would find themselves in a sort of donut hole: Ineligible for Medicaid but also too poor to qualify for federal subsidies. That's the area represented in orange below:

Analysts at the Urban Institute ran the numbers for everyone eligible for the Medicaid expansion -  both childless adults and parents - and found that 76 percent live below the poverty line. That means they would fall into the orange area above, ineligible for private or public assistance in obtaining health care coverage.