The Council of West Knox County Homeowners is a non profit, I am not 100% sure they are precisely a 501 (c) 3, but typically all non profits are forbidden from endorsing or being involved in political races.
BUT, here comes an email from the organizations Corresponding Secretary announcing the organizations favorite for a County Commission Primary and encouraging all to help him.
Mr. Hornback,
This organization could be a 501(c)(4) nonprofit. (c)(4) nonprofits include “social welfare organizations,” which this organization could be considered. (c)(4) nonprofits are allowed to participate in the political process so long as such involvement are not the primary focus of the organization. I have included a link which you might find useful.
https://www.irs.gov/charities-non-profits/other-non-profits/types-of-organizations-exempt-under-section-501c4