Predictably, everybody’s arguing about the new Quinnipiac poll showing a big drop in President Barack Obama’s support among Jewish voters (see yesterday’s Political insider blog item on the subject here).

An official with the National Jewish Democratic Council (NJDC) sent a strongly worded email (translation: an emailed slap on the wrist)  objecting to my item, arguing that the tiny sample size makes the Jewish numbers “crazily unreliable.”

The Jewish Dems have a point – but are also missing one.  Yes, sample size is small, the margin of error great. These are numbers I wouldn’t take to the bank.

But the Jewish drop – which, as I pointed out, still leaves Jews as the religious group MOST supportive of Obama and the Democrats – is also consistent with what almost every independent political observer has seen.

And it’s about what you’d expect in a Jewish community that generally mirrors national trends in politics, but always from a more Democratic perspective. In other words, when a Democrat’s numbers plunge, Jewish support drops too, but not as much.

Over at JTA, Eric Fingerhut offers a more detailed analysis that makes a lot of sense to me. His beef: “When looking specifically at the Jewish number and the findings from three previous surveys, the swings are so dramatic to not make any sense.”

That reflects the flaw in most polls that look at religion and politics.  Except in the  biggest surveys, the sample size for a Jewish community that makes up only 2 percent or so of the overall population is bound to be low, making the numbers less reliable.

That gives political advocates across the spectrum fodder for objecting to numbers they don’t like, while touting the surveys that suit their partisan goals.

While we’re at it, Republican Jewish Coalition director Matthew Brooks, in his press release, wrote that the poll showed that “the Jewish community has been troubled by the efforts of this administration to pressure Israel on the issue of ’settlements’ and has raised questions about the sovereignty of Israel over a united Jerusalem. These and other actions by the President have fueled the growing ‘buyers’ remorse’ on the part of Jewish voters.”

Nice try, Matt, but there’s nothing in the survey about Jerusalem, settlements, Israel or foreign policy.