Born in Detroit, Bommarito became a machinist at the United States Rubber Company in Akron, Ohio, and in 1940 he joined the United Rubber, Cork, Linoleum and Plastic Workers of America union.
In 1942, he joined the United States Marine Corps, and he served in the Pacific during World War II.
[1] After the war, Bommarito returned to the Rubber Company, and in 1948 he was elected as treasurer of his local union, rising to become its president in 1957.
He later centralized bargaining across the four largest rubber companies, something which proved highly controversial with members, but led to improved pay and conditions.
He also served on the Committee for National Health Insurance, and on the board of the Salvation Army.