The link below will take you to the section of the U.S. federal tax code (the code that gives non-profits their tax-exempt status) that describes the limits imposed on non-profit 501 (c) 3 organizations interested in doing voter/membership outreach and related partisan political activities.
Examples are provided for many of the restrictions. Note that violating these restrictions could lead to a revocation of tax-exempt status. For more information and consultation, please contact Nancy Chen firstname.lastname@example.org at Alliance for Justice www.afj.org, an organization focused on advising non-profits on federal tax code lobbying and advocacy restrictions.
As many minority non-profits, specifically 501 (c) 3 no-profits, work to educate and mobilize their respective ethnic communities to go out and vote this coming November 4, it is important to bear in mind what the limits are.