An internal IRS document provides additional clarification - FSA 1993—0921—1 Federal Income Taxation of Churches
Article summary. In order to maintain their tax—exempt status (for federal income tax purposes), churches and other religious organizations must comply with several requirements specified in section 501(c)(3) of the tax code. One of these requirements is that the organization must not participate or intervene in any political campaign on behalf of (or in opposition to) any candidate for public office. A violation of this limitation can result in revocation of tax—exempt status. A recently released internal IRS memorandum addresses this important limitation, and provides helpful insights into the thinking of the IRS national office.
The participation by churches and church leaders in political campaigns is an American tradition. Common examples include: ...