Cooper actively supported various social reform movements, including abolitionism and the promotion of public education. He believed in using his wealth and influence to address social inequalities.

At the age of 85, Cooper accepted the presidential nomination of the Greenback Party, which advocated for a monetary policy based on paper money rather than gold. His candidacy was largely symbolic but highlighted his commitment to economic reform.

During the 1876 presidential campaign, Cooper travelled and spoke out about social issues and reform. He did not receive many votes but brought the Greenback Party's ideas to the public.