A mass mailing is one method for delivery of information, though it may not always be the best choice. When making a choice on what media form to use, refer to the outline of available methods.
From the Acceptable Use Policy 19.4.g.: Refrain from prohibited personal uses. Information technology resources, including the University's electronic address (e-mail, web), shall not be used for personal commercial gain, for charitable solicitations unless these are authorized by the appropriate University officer, for personal political activities such as campaigning for candidates for public office, or for lobbying of public officials.