 In 1928, Nicholson married Marian Leila Massey.Nicholson served as a United Church of Canada minister at Hudson Bay Junction, Saskatchewan and had a farm in Sturgis, Saskatchewan.He became an organizer for the Co-operative Commonwealth Federation in 1935, became the national treasurer of the party in 1942 and from 1944 to 1950 and served as a CCF Member of Parliament from 1940 to 1949 and again from 1953 until his defeat in 1958.