Why do I need to be an ACA member to contribute to the ACA-PAC?

Federal elections law generally prohibits political contributions by a corporation or other organization. However, contributions to a political action committee, like ACA-PAC, are permitted provided, among other things, a supporting organization (here ACA) is soliciting only from its members. Contributions from someone other than a member would fall outside the exception and could not be used to further the goals of such organization.