Alexander McNair wasn’t especially well-educated, but he became a judge and a governor of a territory and then that same area when it became a state, so he must have had something going on besides high-level friends.
Then again, as governor, he wasn’t able to get a ton of stuff done, and when his term ended he took on a Federal job just for the money. So, for a guy who spent so much time in the “Show-Me State”, he didn’t really have much to show.