American Jews will line up behind Obama. Their religion is liberalism. That is all.
You are painting with too broad of a brush. There are many American Jews, including those here on FR, who detest Obama as much as anyone else, and for good reasons. Just this week, for example, radio talk show host Mark Levin, who is Jewish, announced that he will file a suit challenging the constitutionality of the ObamaCare bill if it should "pass" the House and be be signed by the Anointed One.