Is the Southern Firewall in trouble? Sanders doing well among Whites in SC (updated)

So I was playing around with projections, and happened across the Yougov and PPP SC polls. All anyone cares about are the toplines – but I looked at the cross-tabs.

All anyone has been talking about when it comes to the South is the African American vote, and how Bernie is going get killed.  And it is right to focus on that.

But I think there was an assumption in that discussion that a democratic socialist would get killed among whites too.

But here is the thing: in PPP he splits the SC white vote and in Yougov he wins it.  It is kind of mind-blowing that Bernie would do that well when he still isn’t known that well.

So I modeled the southern 3/1 primaries. A funny thing happened: Clinton only nets 67 delegates among all 7, and Sanders could reduce that significantly in other 3/1 states.

If the Sc cross-tabs hold, the southern firewall isn’t going to be much of a firewall.

I can’t get the image to show, but it is here:
http://s140.photobucket.com/user/fladem/media/delegatecplit_zpsjvk1cvxg.gif.html

[Update]: the math is simple but repeated over and over. So I predicted VA would be 49-39, a new poll has it 52-40. You see a similar breakdown in the new Suffolk national poll, and in the new SC poll.