It's tough, because there's a lot of overlap between groups that advocate for Jews and groups that advocate for Israel. The difficulty in conceiving metrics which can account for 'soft power', like influence via political and popular media, is (in my estimation) part of what makes people so attracted to bizarre consipiracy theories on the matter. Even trying to formulate such metrics (on any topic, not just Israeli affairs) quickly leads to sounding like one has arrived at the far side of weird. I don't have the right answers, but raw dollar input in the lobbying industry simply can't be the whole story; humans are more complex than "money in, opinions out".

> I think that's a fair critique. Do you have any alternative metrics for evaluating the "most powerful" lobbies in the US?

It appears to be the only one able to consistently get US citizens working for US employers in US soil fired for expressing opinions about a conflict halfway to the other side of the globe. If it were Russia or Ukraine lobbists getting US people fired, probably the FBI would be already indicting people for foreign interference in domestic matters.