In GA, you don't declare at the primary level until you tell the voter volunteer which ballot ya want. That won't pigeonhole you, as you can ask for the other ballot next year, or even in run-offs in the same year. You don't really "register" with either party at a polling place - ever. Lots of crossover voting in this state, which makes things a tad more interesting in the opening phases.
I'm all fore getting voters out there. My issue is when you bus people in and buy their votes for a few packs of ciggies - a la Gore.