It's not Jewish, it's pro-Israel (American Israel Public Affair Committee). Israel is a foreign country whose interests might be conflicting with those of the US. That's different, don't you think?
> OP's mention of "Dual Citizens" clearly meaning Jews
"Dual citizens" clearly means "dual citizens".
If the OP had the information that many Jews in Congress were dual citizens, he was wrong- although in fairness it's an understandable false belief when you have US politicians coming to Congress wearing their IDF uniform or propose laws to give IDF veterans the same benefits that US veterans receive.
> concerned with AIPAC and not the other foreign PACS. Wonder what the differentiating factor is?
Just look at the the first PAC in the list you mentioned: it's Accenture. Classified as foreign because their headquarter is in an empty office of a tax haven. AIPAC is not even in this list: it's in the "ideology/ single issue" list, where it stands as the only pro-<some country> PAC in the list (and the 4th largest).