Let’s see here:
New York of course is TRUMP’s home state and has an enormous ethnic Irish and Italian population in both the NYC metro area and upstate who have been overwhelmingly favourable to TRUMP’s message of populistic nationalism. It is this Catholic working-class/lower middle-class who makes up the core of Middle American Radicals who is the Donald’s natural constituency. Of course, polls here have him leading by overwhelming margins, exceeding 50% in every recent poll.
Pennsylvania has a large share of ethnics as well as well a significant Scotch-Irish population who also are naturally very responsive to TRUMP’s populist style. Not to mention Pennsylvania has been economically devastated by deindustrialization. One need only look at coal country around Pittsburgh to verify this truth. Similarly TRUMP has maintained a lead in all recent polling.
Everything I said about New York applies to New Jersey as well.
Now California is the most difficult case because admittedly it has undergone significant white flight and thus reduced significantly the number of white working-class and lower middle-class individuals which has strengthened the position of wealthier professional types in the remnant of the California Republican Party. Nonetheless if returns from Arizona and Nevada indicate anything, it is that any states with a large Hispanic population leads to a polarization of the immigration issue and in turn, to Republican voters supporting the most openly nativist candidate in the race-namely Donald TRUMP. Remember, this is the same state that passed Prop 187 two decades ago. Also the poll numbers have Donald in the lead.