Mayes Middleton is President of Middleton Oil Company, an independent oil and gas company. He also runs ranching, cattle, and farming operations. Mayes and his wife, Macy, have four children: Connor, Christian, Matthew, and Martha Ann. Mayes and Macy support numerous local community organizations and faith-based charities throughout the Galveston-Houston region.

Prior to serving in the Texas Senate, Mayes served two terms in the Texas House of Representatives, representing Chambers and Galveston Counties. During his last term in the Texas House, Mayes served as Chairman of the Texas House Freedom Caucus.

Now in the Texas Senate, Mayes represents Senate District 11, encompassing portions of Brazoria, Galveston, and Harris Counties. Throughout his time in both the House and Senate, Mayes has consistently ranked among the top most conservative members of the Legislature. Senator Middleton currently serves as the Vice Chairman of the Subcommittee on Higher Education and as a member on the Senate Committees on Administration, Business & Commerce, Education, Jurisprudence, and State Affairs.