In 1921, Cowan's husband James was elected mayor. When he died in office, she was appointed to fill his term. She was a member of the local chapter of the
League of Women Voters and was the local representative to the 1925 national convention. Cowan ran to be mayor for a second term, although spent no money on her campaign, and did not actively campaign for office. Cowan lost the election. According to an account in 1929, "Mrs. Cowan served during the closing months of 1924 and until June 1925 when she yielded the reins of office….to Mr. Walter H. Blair, elected in May 1925." In the 1930s, Cowan was active in
Democratic politics in
Washington, DC. By the late 1930s, Cowan was a supervisor with the
Works Progress Administration. == Personal life ==