Erlandsen worked for 23 years as a paper maker for Escanaba Paper Company. He played a key role in organizing a credit union for the company in 1941, and served as the elected treasurer and manager of the credit union until 1948. On November 2, 1948, Erlandsen was elected to the Michigan House of Representatives where he represented the Delta County district from January 5, 1949 to December 31, 1964. On November 4, 1964, Erlandsen was again elected to the Michigan House of Representatives where he represented the 107th district from January 13, 1965 to December 31, 1966. Erlandsen was defeated when he sought re-election in 1966, and again in 1968. In 1956, Erlandsen was a delegate to the Democratic National Convention.