This is true. Some of those counties have Democrat majority voter registration but reliably vote 70% or more Republican in statewide and federal elections. And the local Dems they elect are actually more conservative than Republicans in most parts of the country.

The registration patterns and party affiliations in those counties are starting to change, though. This is partly due to local Republican parties getting their acts together and running better candidates and partly due to people seeing how nutso the national Democratic party is and not wanting to be associated with them.