President Barack Obama may claim (somehow) to know more about Judaism than any president in American history, but the latest Gallup poll of Jewish voters suggest he has less support from the Jewish community than his recent Democratic predecessors. 64% of Jewish registered voters would vote for Obama--down 10% from the 74% who expressed a similar preference before the 2008 elections. That is the worst performance among Jews for a Democratic presidential candidate since Michael Dukakis and George H.W. Bush faced off in 1988.
On the other hand, Gallup's numbers agree with other polls that show Obama's support rising slightly among Jewish voters since September 2011--the month when outrage at Obama's poor record on Israel fueled an historic victory for Republican Bob Turner in a heavily-Jewish, traditionally Democratic congressional district in Brooklyn.
A word of caution: Gallup tested registered voters, not likely voters, and therefore likely oversampled Democrats. Moreover, Jewish voters, as a group, do not play a significant role in national elections except in a few swing states (Florida and Pennsylvania, for example), and Gallup's sample size appears too small to have measured state-specific trends. If anti-Obama voters in the Jewish community are particularly motivated, that might have an impact on the final vote.