The exempt function income of a political organization is income the organization sets aside for use for its exempt function that was received as one of the following:
- 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 § 513(f)(2).