Nearly four million people who were supposed to be helped to health insurance through the Affordable Care Act remain uninsured today because they earn too much to qualify for Medicaid and not enough to qualify for the reform law’s health insurance subsidies.

When the law was passed in 2010, it was supposed to provide Medicaid coverage for those earning up to 138 percent of the federal poverty level and offer subsidies to other low-income earners.  But when the Supreme Court made the reform law’s mandatory Medicaid expansion optional for states and some states chose not to expand their Medicaid programs, nearly four million people found themselves wedged between eligibility for Medicaid and eligibility for subsidies, with no help forthcoming.

Among the four million, more than half work at least part-time and two-thirds reside in a household with at least one wage-earner.  Most work for small companies that are not required to provide health insurance for their employees and many earn the minimum wage.  Many are single adults.

Many of the people in this coverage gap live in communities served by private safety-net hospitals and turn to those hospitals for care when they need it.

The Washington Post has taken a look at the challenges these low-income and often medically vulnerable people face living in states that have chosen not expanded their Medicaid programs.  See its report here.