The New York Times does an amazing job at data journalism within its Upshot section. This interactive map of the uninsured, by Quotrung Bui and Margo Sanger-Katz, is pretty amazing, especially when one considers that Wisconsin, nominally a non-expansion state, already provided significant coverage overlapping with ACA. Why is Medicaid expansion important? Go to the New York Times link and see for yourself. Cross the Kentucky border into any non-expansion state. If anything, this non-population-weighted-map understates the importance of Medicaid expansion, since many of those huge purple counties out west have very few people living in them. Ninety percent of the adults who fall in the Medicaid gap live in formerly-segregated states.
PS this amazing GIF showing how patterns have changed since 2013 makes me both proud and sad regarding our country.