Martin A. Nelson earned a law degree in 1916 and practiced law in St. Paul, Minnesota, before serving in World War I as an aviator and aviation instructor. After the war, he practiced law in Austin, Minnesota, from 1919 to 1944, and served as a trustee for St. Olaf Hospital for 22 years, including a decade as board president. Nelson held various political roles, including being a delegate to Republican National Conventions and running for governor and the U.S. Senate. He was appointed a state court district judge in 1944 and later served on the Minnesota Supreme Court from 1953 until his retirement in 1972, which led to the law mandating retirement for state judges at age seventy.

Martin A. Nelson's political career is marked by a blend of steadfast judicial service and unconventional political maneuvers. His tenure on the Minnesota Supreme Court and his fight to stay past the retirement age reflect a commitment to judicial independence, while his independent Senate run and fluctuating party affiliations suggest a willingness to challenge traditional political boundaries. Nelson's approach to policy issues remains largely unexplored, but his strategic choices hint at a calculated balancing of regional interests and personal convictions.