Richard McMullen was born in 1868 in Porters, near Glasgow, Delaware, and later married Florence Hutchinson with whom he had three children. He began his career as a farm hand while attending Goldey Commercial College. McMullen founded the Standard Kid Company in 1917, eventually rising to the position of general manager for the Allied Kid Company in Wilmington. He served on the Wilmington City Council and various commissions before being elected Governor of Delaware in 1936, where he managed public works projects during the Great Depression and revised the state's "blue law."

Richard McMullen's political identity is marked by a blend of progressive labor policies and pragmatic public works initiatives. His endorsement of the Fair Labor Standards Act reveals a commitment to workers' rights, while his public works projects during the Great Depression suggest an equally strong focus on infrastructural development. This juxtaposition hints at a nuanced approach to balancing economic reform with tangible progress. McMullen’s revision of Delaware’s “blue law” to ease restrictions on Sunday activities further underscores his pragmatic yet forward-thinking governance style.