Note: The Center categorizes individual contributions to candidates as being ideological only under strict conditions. For example, a contribution to a candidate will be considered to be pro-Israel only if the contributor gives to a pro-Israel political action committee AND the candidate has received money from a pro-Israel PAC. Thus, the contribution figures attributed to ideological groups, including pro-Israel and pro-Arab interests, may be artificially low.
However, as I showed in the original post, even if you double, or even triple, the amount contributed by pro-Israel interests, it still doesn't compare to the big guns - corporations and unions. Note that my original post had the easier task of debunking conspiracy theories claiming that the Israel lobby is the biggest of them all. The numbers show that to be far from true.