It's hard to say for sure, since there currently aren't that many swing voters in this state. Geographically speaking, Democrats need to make significant inroads in Upstate SC in order to be competitive statewide (for example, under the current political alignment, a hypothetical Democratic statewide win would involve them not losing Greenville County by more than 8 points or so).
This is correct, but obligatory pedantic point that this region is the "Upcountry", not "upstate" (much like Charleston and coastal environs are the "Lowcountry"). Source: my undergrad advisor was South Carolinian
The Upcountry has always been whiter and more industrialized than the rest of the state, as is immediately apparent in any election map from about 1948 to 1968 having Democratic strength concentrated among mill workers and hill people, but within the old Southern agrarian focus and lack of real industrial policy (now compounded by Taft-Hartley et al) there was not much of a labor movement to speak of nor any opportunity for them to advance their goals. Post-Reagan and all those realignments later it then became a center of outsourcing by East Asian industrial corporations who somewhat revitalized this aspect of its history, but again within a context of barren labor protections now doubly so in which the industrial workers are/were content as lumpenproles getting swept along by resentment politics as opposed to their material interests. And of course Southern racialized suburban resentment is in full swing here, especially in Spartanburg.
