Nevada is not South Carolina. But I think if you look at the results carefully there, it is at least consistent with the idea that Biden should be a fairly clear favorite in South Carolina
If you model the result in South Carolina, based on the results in Nevada, here's what you get:
Biden 36
Sanders 21
Warren 14
Steyer 11
Buttigieg 10
Klobuchar 7
Biden 36
Sanders 21
Warren 14
Steyer 11
Buttigieg 10
Klobuchar 7
This is driven by Biden's easy to overlook strength precincts where black voters make up a majority of Democratic voters in Nevada. There aren't many of them, but it's fairly obvious on the map (north side of Las Vegas) and in the data 
Of course, there aren't many of these precincts in Nevada. And black voters in NV aren't the same as in SC, and so on.
But the same could be said for Iowa and Nevada and Nevada Hispanics, and yet the same approach yielded reasonable results
But the same could be said for Iowa and Nevada and Nevada Hispanics, and yet the same approach yielded reasonable results
Also, correction; I typed Warren/Steyer backward. The actual estimate based on NV:
Biden 36
Sanders 21
Steyer 14
Warren 11
Buttigieg 10
Klobuchar 7
Biden 36
Sanders 21
Steyer 14
Warren 11
Buttigieg 10
Klobuchar 7
All the same caveats that applied before NV apply here. It's a fundamentally different campaign from state to state. Steyer has been a bigger player. And if Sanders got momentum out of NV, he might carry it into additional strength in SC, just as he may have in NV from IA
But it does strike me as quite notable, that even as late as NV, Biden was still winning majority black areas by enough to carry South Carolina. If that was true then, I'd still expect it to be true on Saturday.
