Maybe in the 2030s, as the AA population grows, older conservative whites die off and are replaced by young liberal whites, the big cities become more dominant and transplants from liberal states arrive.
*I come into this post NOT knowing the answers to these questions; I am not being facetious.*
1) Is there any indication that the Black population in SC is growing faster than the White population? If so, is there evidence to believe this will continue long enough for the state to become competitive? If not, is there evidence that this will start to be the case?
2) I think it's a decently fair assumption that these older, conservative Whites who die might be replaced with MORE older, conservative Whites. Every year, more Whites from a generation that is fairly Republican retire, and a lot of them end up in places like South Carolina, Florida and Arizona.
3) Going off of point #2, is there really a trend of a lot of young, liberal Whites moving to SC? How would one even track this?
4) The "big cities" wouldn't just have to become more dominant; they would have to become more Democratic. Big difference between a very liberal Atlanta growing and growing and blueing its suburbs to the point that it can outvote its Republican exurbs and rural areas and a situation like Indianapolis, where a Democratic city really isn't that Democratic anyway. I would argue SC is closer to the latter. SC's metro areas might continue to get more and more Democratic AND grow, but you're counting on two things there (rather than just continuing to grow and expand and slowly outnumber the Republican vote).
I really don't see SC going the way of Virginia or Future Georgia.