Here’s a very interesting report from “The Solomon Project.” The main conclusion is that based on election year exit polls, Jewish support for Democrats and liberalism has remained pretty constant since 1972.
If one digs a bit deeper into the report, one learns that current trends suggest that the American Jewish electorate will grow less Democratic in the future. First, unlike the rest of the electorate young Jews
were less likely to vote for Obama in 2008 than were older Jews have been less likely to vote for Democratic presidential candidates over the least three elections. Indeed, about 75% Jews under 30 voted for Obama the Democrat (compared to about 85% of the over-60 crowd)* [by the way, this renders the premise behind Sarah Silverman's "Great Schlep" rather ridiculous, no? Maybe the alter kockers in Boca should be going up to Pennsylvania and Ohio to persuade their grandchildren to vote Democrat, rather than vice versa] , not that much higher than the 66% of the general under-30 electorate that voted for Obama (the study tabulates the last three elections together for age]. Second, more religiously observant Jews are significantly more likely to vote Republican and not identify themselves as liberals. A rapidly increasing proportion of the American Jewish population is religiously observant thanks to high birth rates among the Orthodox, low birth rates and intermarriage among the non-Orthodox, and the fact that the generation of at least nominally Orthodox Eastern European immigrants whose children were not Orthodox has almost entirely died out, so for likely the first time in American history Orthodoxy is concentrated among the young.
One other interesting data point I can draw from the study is that Orthodox Jews (and possibly other observant or “religious” Jews) are substantially underrepresented in exit polls, or at least recent exit polls, relative to the rest of the Jewish population. The 2004 results are based on interviews with over 1,500 Jews, and the 2008 results on interviews with over 1,000 Jews. Yet, the report notes that under 50 respondents each year said that they attend synagogue at least weekly.
The majority, I suspect a great majority, of Orthodox Jewish men attend synagogue weekly or more often (women are exempt from the requirement of public prayer but some attend anyway). Given that Orthodox Jews are 10-15% of the American Jewish adult population, and that some Reform, Conservative, and other Jews also attend synagogue weekly, you have to wonder about the accuracy of these samples in reflecting the American Jewish population–surely way more than 50 American Jews per 1,500 attend synagogue at least weekly.
UPDATE: The most recent statistics estimate that 14% of American Jews attend synagogue at least weekly, or at least 5 times the percentage reflected in 2004 exit polls, and at least 3 times the percentage reflected in 2008 exit polls. Given that religiously observant Jews are significantly more likely than their secular peers to vote Republican–indeed, the Solomon Project study cites other studies concluding that most Orthodox Jews vote Republican in presidential elections–it seems fair to assume that the exit polls overestimate the vote for Democrats by several percentage points.