I didn't mean to make it sound like whites and blacks in South Carolina will vote like the ones in New York, just that I find it weird how Quinnipiac's numbers show that the one closed primary that Clinton will underperform her 2008 margin is her home state.
Quinnipiac has been a bit friendly to Sanders. At the same time, if she does underperform her 2008 margin in NY, it might be because the home state effect won't be as strong as it was then, since she isn't currently a senator from there. Also, I fully expect her to underperform her 2008 numbers in KY and OR, also closed primaries.