Consider the vote share of the two main nominees:
Take out the votes for Stein and Johnson, and one gets
Clinton 44/92 = 47.83%
Trump 37/92 = 40.22%
It's hard to see how Hillary Clinton is a particularly good cultural match for Georgia, but it is easy to see how Donald Trump, arguably the worst sort of city slicker possible, is a horrible fit.
https://twitter.com/jbarro/status/761532763526860800?lang=enRepublicans have been doing very well in the South, so there's no room for Trump to improve...
https://twitter.com/Nate_Cohn/status/762303397978525696Also, metro ATL has a highly educated population. The Republicans inside Atlanta voted Rubio strongly.