The exempt function income of a political organization is income that the organization sets aside for use for its exempt function that was received as one of the following four types of income:
- A contribution of money or other property;
- Membership dues, fees, or assessments from a member of the political organization;
- Proceeds from a political fundraising or entertainment event or from the sale of political campaign materials, which are not received in the ordinary course of any trade or business; or
- Proceeds from conducting bingo games that are defined in Code section 513(f)(2).