The Texas Tribune has an interactive data base of poverty Texas that lets you look at poverty by county in Texas.
Viewing raw numbers shows that there are large numbers of people living below the poverty level in the major cities. However, that can create the impression that rural areas are relatively prosperous.
Looking at the percent below poverty level reveals that rural areas often have a higher rate of poverty.
You can click on each county and see some pretty extensive statistics on poverty in that county. It’s a great tool for thinking about public policy in Texas.