Mississippi has around ~338,000 residents enrolled in ACA exchange plans, 98% of whom are currently subsidized. I estimate they also have another ~14,000 unsubsidized off-exchange enrollees.
Alaska has around ~28,000 residents enrolled in ACA exchange plans, 88% of whom are currently subsidized. They also have an unknown number of off-exchange enrollees in ACA-compliant individual market policies. Overall, including net attrition, I estimate their total enrollment both on & off exchange to be perhaps ~27,000 or so.
Kansas has around 200,000 residents enrolled in ACA exchange plans, 94% of whom are currently subsidized. I estimate they also have another ~6,000 unsubsidized off-exchange enrollees.
Missouri has around ~417,000 residents enrolled in ACA exchange plans, 94% of whom are currently subsidized. I estimate they also have another ~3,600 unsubsidized off-exchange enrollees.