Actually, the clerk seemed to believe I was a US citizen but had (or claimed to have) no authority to allow me to vote, other than by provisional ballot. I subsequently had to fax the info page from the self-same passport to the county Board of Elections, and then they allegedly cleared the black mark from my record in the system and designated my ballot to be counted.
In Canada, where I'm from, polling place personnel have the authority to deal with matters on this kind of level. Not in Georgia, apparently.
I agree that it seems like a Republican state kind of issue. In fact, I am silently in violent dissent whenever Georgians fulminate about how they wish the evil federal government would keep out of our state business. As far as I'm concerned, our state government is typically inept or corrupt, and I prefer the federal government any day. If it had been left up to the good folk of Georgia and the kinds of folk they like to elect, we'd still have segregated schools, I betcha.