Coke: 83%
Soda: 11%
Pop: 4%
Other: 2%
Everywhere I've lived has a major "Coke" majority, except LA county which has a significant "Soda" majority.
Personally, I tend to use the generic "soft drink" with an occasional "soda" when I need to be brief. I use "coke" only as a generic for any sort of cola, including Pepsi.
This is almost exactly me, except I also sometimes say "soda pop" in an exaggerated Minnesota accent (but normally under my breath, for fear of becoming an annoying guy who does exaggerated accents in front of other people).