The particularly odd thing is that Hoboken is less Democratic than, say, Battery Park City. But maybe the sort of people who move to Hoboken are more tax-conscious (avoiding NYC income tax) and thus somewhat more likely to be Republicans. I can also imagine the sort of people who put a premium merely on living in Manhattan may be more likely to be Democrats than people who are otherwise demographically identical but fine with living in a similarly urban part of NJ.
I think you're right. The Hoboken demographic is interesting. Too pragmatic/not rich enough for Manhattan, but not hipster enough for Brooklyn.
Brooklyn is best borough...