31% of remaining uninsured are undocumented immigrants or caught in the Medicaid Gap.
Yesterday, after the big quarterly Gallup survey was released showing a total reduction in the uninsured among U.S. adults from 18% in October 2013 down to 11.4% in June 2015, I went ahead and whipped up a more detailed graph which 1) includes the full range starting from 0% (Gallup's official graph cuts off the first 10%, which gives a bit of a false impression of the true situation); 2) includes the 2 key dates: March 2010 (when the ACA was signed into law) and October 2013 (when the ACA exchanges/Medicaid expansion enrollments started); and 3) also includes 2 extremely important color-coded areas: The 3.7 million people caught in the "Medicaid Gap" in 21 Republican-controlled states, and the millions of uninsured, undocumented immigrants nationwide.
These sections are important because there's simply no possible way for the Affordable Care Act to help these groups get insured under current law; it's completely out of the Obama administration's hands at the moment. Unless those 21 states actually come around and expand Medicaid (with or without certain concessions), those 3.7 million people are effectively screwed no matter what. The original version of the ACA, as passed, would have covered them, but the 2012 Supreme Court ruling left that up to the states, so it's in their hands.
As for the undocumented immigrants, that's a different situation. The ACA as passed never allowed this population to receive assistance, whether via Medicaid or ACA exchange enrollment. To the best of my knowledge, these folks aren't legally allowed to enroll via the exchanges even at full price (although they can, of course, sign up directly with an insurance provider if they're able to do so).
When I posted the first version of this graph, I estimated the total number of undocumented, uninsured immigrants at around 6 million even. However, last night I revisited the Kaiser Family Foundation's website to see if their estimates have been modified since the last time I checked (via both methodology tweaks as well as simple population/demographic shifts over the past year and a half), and sure enough, the numbers have jostled around somewhat since then. As a result, it looks like this population is about half a million higher than I had previously figured: Around 6.5 million. Note that this is still a very rough estimate; in 16 states, while KFF has a pretty good estimate of the total number of uninsured not eligible for ACA exchange tax credits, they weren't able to separate out the two groups which make up that number: Legal residents who simply have too high an income to qualify, and undocumented immigrants who aren't eligible at all.
For those 16 states, I used a rough 60/40 split between the two groups, since the remaining 34 states (+DC) are roughly 60/40. This results in just over 6.5 million on the "undocumented immigrant" side nationally.
This is obviously a rough estimate. However, there's roughly 11 million undocumented immigrants total nationally, so 6.5 million would mean appx. 59% of them are uninsured. As it happens, there were appx. 2.55 million undocumented immigrants in California as of 2010, and the latest CoveredCA report states that 1.5 million of those are uninsured...which just happens to be exactly 59%. Since CA is the largest state in the country, that seems like pretty good evidence that I'm in the right ballpark. Florida, with around 825,000 undocumented immigrants, is also at around 58% uninsured. Other large states like Texas have it higher (around 74% uninsured out of 1.65 million total) or lower (44% uninsured in New York out of 625K total), so 60% seems to be a pretty solid rule of thumb for those 16 states.
As I also noted yesterday, when you take into account the fact that the 11.4% in the Gallup survey only applies to adults over 18 (appx. 28 million out of 245 million adults) and the fact that the uninsured rate among children below 18 was only about 8% to start with back in 2013 (around 5.9 million out of 74 million at the time, likely down to around 5 million today), that means the total uninsured population is down to around 33 million nationally.
When you subtract 3.7 million in the Medicaid Gap and the 6.5 million undocumented immigrants, that means the ACA's maximum theoretical remaining uninsured reduction potential is down to around 23 million total.
Put another way, appx. 20% of the 33 million people still uninsured nationally are undocumented immigrants, and 11% are caught in the Medicaid Gap.