A member of the Democratic Party, Gardner worked in the administrations of President Franklin Delano Roosevelt and Harry S. Truman.

He attended North Carolina State University (then known as North Carolina A & M) on a scholarship, where he majored in chemical engineering, was involved in ROTC, played on the football team, managed the baseball team, served as the senior class president, and maintained active membership in Sigma Nu fraternity.

Gardner distinguished himself off the football field as well, becoming one of the most respected members of the Dialectic and Philanthropic Societies at University of North Carolina at Chapel Hill.

The election was likely stolen by the political machine of U.S. Sen. Furnifold Simmons, who, through his lieutenant, A. D. Watts, used racial demagoguery and electoral fraud to favor their candidate, Morrison.

Gardner pushed many of the Brookings recommendations through the legislature, including taking over financial responsibility for roads and schools from counties and the creation of what would become the consolidated University of North Carolina system.

He did, however, push through the legislature a workman's compensation law and successfully mediated a massive 1932 strike of mill workers in the Greensboro–High Point area.

He was an informal advisor and speech-writer for President Franklin D. Roosevelt, who appointed him chairman of the advisory board to the Office of War Mobilization and Reconversion, and later a member of the Joint Anglo-American Commission on Palestine.

The O. Max Gardner Award was established in his will to recognize University of North Carolina system faculty who have "made the greatest contributions to the welfare of the human race."