Why Jewish Senators are blocking Burris appointment?

The same reason as all the others are reacting toward Burris in a negative fasion - Blagojevich's confirmations may not be legal. This is not a Jewish, Muslim, Christian thing at all. The appointor is under investigation for trying to sell the seat, and any person he appoints is suspect as having bought it. The Governor has effectivly screwed any politician by appointing them himself, which may be what he's trying to do.