Tollefson was born in Perley, Minnesota, one of seven children. His family moved to Tacoma when he was two and lived in the McKinley Hill neighborhood. He graduated in 1928 from Lincoln High School, then worked at Hunt and Mottet Hardware to support two of his siblings while they completed their education. He was an enthusiastic amateur athlete.

Tollefson graduated with a law degree from the University of Washington and began practicing law in Tacoma in 1939. In 1952 as a freeholder, he helped draft a new charter for Tacoma, changing it from a Commissioner--Mayor to a Council--Manager system of government. Following adoption of the new charter, he won a seat on the new City Council. The Council appointed him to Mayor. As Mayor, Tollefson worked to shut down commercial prostitution and gambling in the city. He oversaw development of modern sewage treatment for Tacoma, undertook a program of street paving and lighting, and worked to replace the city’s wooden water mains. After completing his term as Mayor, he served on the Council from 1956-1958.

In 1962 he was directly elected Mayor by citizens of Tacoma. In this second mayoral term Tollefson brokered an agreement for joint tenancy of the County-City Building. He successfully lobbied the Washington State Legislature to allow cities and counties to receive a portion of the State sales tax. He led the fight to protect Tacoma’s Green River Watershed by keeping the area closed to the public. He supported completion of the Cowlitz River dams.

Tollefson served on the Executive Board of the Association of Washington Cities. In 1966 he was elected President of the National League of Cities. In these positions Tollefson championed increased intergovernmental cooperation. He organized municipal lobbying efforts in favor of full funding for the Model Cities program.

Defeated in the 1967 election, Tollefson returned to practicing law in Tacoma. He continued in public service as a board member of the Municipal Research and Services Center of Washington. He was President of the Tacoma Lion’s Club and the Tacoma Bar Association.

Tollefson was survived by his wife Edith, his children Nicola, Andrea and Brian, three grandchildren, sisters Agnes Hendrickson and Gyda Langlow, and brother Erling.