What is the ban on political campaign activity?
It is a requirement imposed by Congress for the privilege of being recognized as exempt from federal income tax under section 501(c)(3) of the Internal Revenue Code.
For an organization to be tax-exempt under section 501(c)(3) it cannot ¡°participate in, or intervene in (including the publishing or distributing of statements) any political campaign on behalf of (or in opposition to) any candidate for public office.¡±