Let's dismiss this notion that Sanders only does well among white liberals. Only the white bit is true - whether they were liberal or not was more or less irrelevant.
Margin among white voters by state:
Arkansas: Clinton +27
Georgia: Clinton +17
Texas: Clinton +16
Tennessee: Clinton +15
Virginia: Clinton +15
Alabama: Clinton +12
South Carolina: Clinton +8
Iowa: Clinton +3
Massachusetts: Sanders +1
Nevada: Sanders +2
Oklahoma: Sanders +20
New Hampshire: Sanders +24
Vermont: Sanders +73
Lets dispel the notion that Sanders does well among whites. He does alright with them, but he loses them as much as wins them.