States with the highest rates of uninsured residents are among the least likely to have expanded Medicaid or to establish state-based exchanges under the Patient Protection and Affordable Care Act.

That is the conclusion that Gallup pointed to Friday in sharing the results of its latest analysis of how Obamacare is changing health care in the U.S. Yet even with the reluctance of many red states to throw their support behind healthcare reform, Gallup said it has seen evidence that the act is slowly but surely taking hold.

Gallup found that four of the five states with the highest percentage of citizens without health insurance — Texas, Florida, Louisiana and Mississippi — haven't expanded Medicaid coverage or created a state insurance exchange. Arkansas, the other state on that list, has expanded Medicaid and set up an exchange, thus potentially setting itself up to be voted out of that club.