Fundamentally, what distinguishes Presley from Hood? As a longtime incumbent, did Hood come off as "too establishment"? I also see some comments upthread that Hood's sincerity as a social conservative was in doubt?
The main difference is not on him, but on Reeves. Now he's the incumbent and comparably unpopular thanks to scandals surrounding the state executive office.
He's not utterly disastrously unpopular like Matt Bevin in Kentucky became though, and that's probably all he needs to hold his seat. You have to almost be actively trying to lose in these deep red southern states for the D opponent to become seriously competitive.