His birth mother was Portuguese and his birth father Native American, of several tribes, including Northern Cheyenne.
He has been US judo champion three times, won the Pan-American Games gold medal for judo in 1963 and captained the US judo team at the 1964 Olympics; he has also written a judo training manual. He entered the Colorado state legislature in 1982, the US House of Representatives in 1987 and the US Senate in 1992; he is the only Native American currently (1998) in Congress.
His adoption or fostered status is unsure. He appears on several lists of famous adoptees, but other sources do not confirm this. Vance Opperman said on 14 April 1997, (reported in http://www.amexp.org/publications/adoption/adoption1.htm): "The senator speaks personally and very movingly of his experience with his foster family and credits them with much, if not all, of his success." Another source, http://bioc09.uthscsa.edu/natnet/archive/nl/9308/0284.html, states: "Campbell ... was raised in a Catholic orphanage." The article in Current Biography Yearbook states that his mother had TB and his father was an alcoholic, and the strain of working and raising the family was too much for her. She placed the children (Ben and his older sister) in an orphanage in Sacramento in 1939. During the 1940s she reclaimed them. His own official biography for the US Senate does not mention anything relevant about his childhood.
The National Adoption Information Clearinghouse lists him as an adoptive parent, but I have not found any independent confirmation of this.