Thirty years ago, the states with the deepest poverty were all clustered in dixie. But the rest of the country has been playing catchup.
So how did poverty stop being a Southern specialty? You've had, deindustrialization in the Midwest and Northeast. And you've had fast growing Hispanic populations, which tend to be poorer, in California, Nevada, Arizona, and Colorado (as well as North Carolina and Georgia, which could explain their presence on the list above). Meanwhile, the Southeast has made some economic progress by attracting foreign manufacturing, among other efforts.