A person near the top of this list asked how AFA can know that they have 3.3 million supporters….I’m actually glad that someone asked this question instead of blindly accepting numbers. However, the AFA does have a way of knowing the number of their supporters….While I DON’T work for AFA and therefore can’t guarantee that a certain method is used, I DO know that they have a mailing list (not a spam list; you have to sign up for it)….Also, this isn’t the only action which AFA is taking in the world….Letters to Senators and Representatives and the signing of other petitions often (if not always) require information such as your email address and zip code and city and the such….also, there are financial contributors and other people who offer support by way of services (the people who run AFA, as well as perhaps others).
Let me say again, “I DO NOT WORK FOR AFA” I am a supporter of AFA, but I don’t know EXACTLY how they can number their supporters, but it is certainly conceivable that, by the ways mentioned above, a compilation, or at the very least a count, could be created.
I hope that I have helped to answer your question. 
