Ilya Somin tries to explain why Jews vote Democrat. He disagrees with other Jewish explanations, such as Norman Podhoretz's and Irving Kristol's.
These opinions confirm that American Jews have been voting overwhelmingly Democrat for a century, but their theories are filled with contradictions. Jews hate the Religious Right, but that could only explain the last 30 years or so, at most. The cause does not seem to be any religious teaching, because the Orthodox Jews are not so Democrat. Jews are not necessarily opposed to conservatism, as they heavily supported Margaret Thatcher. Explanations based on income, education, urban living, etc. are unconvincing. Nor is it based on support for Israel, as Republicans usually support Israel more than Democrats. Other theories involve Jews foolishly voting against their self-interest. Kristol calls it "cognitive dissonance".
Explanations by non-Jews are always denounced as anti-semitic.
Jews are only about 2% of the USA, but the Democrat Party would be dead without them. Marxist and other more radical leftist movements would not exist without Jews.
Whatever the reason, it seems clear that Jews will vote for Barack Obama in 2012. So will the blacks, single moms, and food stamp recipients.