Marques entered public office in 2018, winning the Republican primary runoff and then the general election for House District 91, which covers parts of Coffee County and surrounding areas. He was re-elected in 2022, receiving 98.5% of the vote in the general election. His current term is set to end on November 4, 2026.

During his tenure in the Alabama House of Representatives, Marques has served on several key committees. For the 2023-2024 legislative session, he is a member of the House Health Committee, reflecting his interest in healthcare policy. He has also been involved in sponsoring and supporting legislation aimed at making Alabama more accommodating for military families, including an insurance exemption for active duty servicemembers signed into law by Governor Kay Ivey in 2023. Marques has emphasized the importance of supporting military families and reducing bureaucratic obstacles for them, aligning with Alabama's broader goal of being a military-friendly state.