Georgia is changing demographically, but like most southern states, it is a state that is really polarized on race.
What makes Georgia different from Alabama or Mississippi is Atlanta, and how it has become more educated over time and how it has been a magnet for POC.
Put another way, the floor for either party at this point is probably around 45-46%. And the battleground is on two things: turnout and suburban voters in ATL. Walker's antics will not help him, but there is a built in floor of support for better or worse.