When will South Carolina turn blue?

[Fmr. Pres. Duke]

I don't see SC turning purple anytime soon, much less blue. We turned even more red than we were before in 2022. McMaster won by almost 20% even though I felt Cunningham was a good candidate for the Democrats. I think we are seeing a Florida effect here where a lot of people moved here during the pandemic because McMaster was almost as radical as DeSantis when it came to going against Covid mandates and precautions. We basically opened up fully in May 2020 aside from closing bars at 11pm.

My home city of Charleston continues to shift more and more blue, but the rest of the state continues to trend GOP. You basically have Charleston and Columbia as the only Democratic counties in the state, and neither are big enough to override the massive GOP margins they get in other counties.

[Fmr. Pres. Duke]

Probably only when there's some kind of really large-scale realignment? South Carolina's lean relative to the country has remained really constant in the 21st century, and the demographic trends of the state as a whole don't seem particularly conducive to a Democratic trend. (It's hard to say how much weight to put on 2022, because it was so state-specific, but the Red Wave did hit South Carolina, as some posters have noted). Also, South Carolina really doesn't have a booming metro area like Nashville, and even then it's not like Tennessee is turning blue anytime soon.

South Carolina/US/South Carolina-lean:
2000: R+16/D+0/R+16
2004: R+17/R+3/R+14
2008: R+9/D+7/R+16
2012: R+11/D+4/R+15
2016: R+14/D+2/R+16
2020: R+11/D+4/R+15

This is actually one of the most consistent states in America, relative to the national environment! (Also, relative to the US as a whole, the worst GOP performance in South Carolina was 2004, and not one of the more recent Trumpy elections where they weakened in the Sun Belt. This is mostly attributable to South Carolina being heavily black and so having a relatively high Democratic floor, but...still).

There is clearly blue trends in Charleston. It was regularly voting for Republicans pre-Trump and Obama barely won it both times. Now it’s gotten blue to the point that the red suburban part actuallly had a Democratic congressman for a term.

Sure; here are the same numbers for Charleston County:
Charleston County/US/Charleston-lean:
2000: R+7/D+0/R+7
2004: R+5/R+3/R+2
2008: D+9/D+7/D+2
2012: D+3/D+4/R+1
2016: D+8/D+2/D+6
2020: D+13/D+4/D+9

So this is a pretty monotonic Democratic trend (except for the Romney campaign; in a lot of places Romney really only slowed the suburban shift, but in Charleston he outright reversed it, which is interesting), but it's a big state outside of Charleston. Here are the same numbers for Horry County, where Myrtle Beach is (which is growing faster than Charleston):

Horry County/US/Horry-lean:
2000: R+16/D+0/R+16
2004: R+26/R+3/R+23
2008: R+25/D+7/R+32
2012: R+29/D+4/R+33
2016: R+37/D+2/R+39
2020: R+33/D+4/R+37

So Biden actually reversed the trend in Myrtle Beach, but it's still significantly more than twice as red as it was in 2000, and growing faster. Plus the rural Black Belt as a whole has been gradually trending Republican. (But Columbia has also been trending Democratic, since that's another 'real' metro area). It all adds up to a state that isn't going anywhere.

Outside of Charleston and Columbia, there are no Democratic strongholds in SC. Greenville and Myrtle Beach are big Republican basestations. Charleston has seen a lot of liberal whites move in in the last decade or so even though the county has gotten whiter. The GOP has also lost a lot of moderates who flipped parties with the arrival of Trump.

That is what makes SC different than Georgia. If all of SC's urban areas were Democratic strongholds, the state would be more competitive, but that's not the case.