Several of the big Dem urban areas, like SF and Boston, practice what is a form of economic red-lining where they make sure the price of living there is so high that it keeps out certain elements (... AHEM..... Blacks, Latinos, etc...) that the lily white liberals don't want in their neighborhood. Jews generally have money so they can't keep them out in the same manner, they just make it where they aren't included in the activities of the more affluent. They acquired the name "limousine liberals" in the late 60's.
Much to the chagrin of the primitives, they also have great influence over the Dem party.
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