That's the question being pondered from some fairly thoughtful discussion at American Thinker back in 2008 to some flame throwing from Eric Alterman just recently.
I expressed skepticism when a poll was released several months ago showing Jews moving away from Democrats, and while I have yet to see reliable data from the election (Alterman's data is far from convincing), I'll accept that Jews voted for Democrats at a higher rate than non-Jews.
Anecdotally, I've heard from many Jews that they are sick and tired of the Obama administration and are voting against Obama, but of course I don't claim to circulate among Obama supporters of any religion.
So even if the hold is lessening somewhat, it still seems to be true that Jews as a whole are in the tank for the Democrats.
There are some superficial explanations, such as the predominance of Reform Judaism, which for as long as I can remember (say, 40+ years) has been a branch of the liberal party, and the liberal party for the past 40+ years has been the Democratic Party.
One also could point to group think -- Jews tend to be present in large numbers in otherwise liberal districts, so liberalism among Jews is pretty typical for such geographic regions, not particularly a Jewish phenomenon.
There also is a tendency among liberal Jews to equate conservatism with Christianity, and the two with anti-Semitism. Just read Alterman's piece linked above for a finely distilled version of fear of Christianity.
None of this makes any sense to me. Whatever anti-Semitism has existed in the United States among Christians is dwarfed by worldwide anti-Semitism among Secular Leftists and Islamists. As I've written before, since at least since the 1940s American Christians have been about the only thing standing between Jews worldwide and the abyss, and that remains true today.
At the end of the day, there is no logical explanation or justification for the phenomenon of American Jews voting disproportionately and consistently for Democrats. It's irrational, and let's just call it that.
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