I figure Obama will probably carry the Jewish vote in 2012 by the same or similar percentages as in 2008. Where he’ll get hurt politically is in the overall turnout numbers. I might be wrong (I often am, lol), but I think Obama is going to have a lot more folks inclined towards “sitting this one out” in 2012.
Assuming he will run - which is still an issue - the guess here is that his percentage of the Jewish vote next year will be much less: somewhere in the 50s.
BTW, his reported 78% of the Jewish vote in 2008, though widely accepted by political gurus, was probably overstated by perhaps as much as 10 points because it was the product of statistically flawed polling techniques.
Gallup's poll results in general have tended to overstate the strength of Democrat politicians and policies because of sampling technique errors as well.