Butcher began to train dogs at age 16. By 1972 she had moved to Colorado, where she attended Colorado State University in Fort Collins and raced a group of 50 Alaskan huskies owned by a local musher. Butcher moved to Alaska in 1975 to start her own kennel. A serious athlete from the outset, she broke onto the international mushing scene in 1979 after driving a team of huskies to the top of Mount McKinley.

Butcher first entered the Iditarod Trail Sled Dog Race in 1978. The roughly 1,100-mile (1,770-km) Iditarod is the longest and most physically challenging of all sled-dog races (dogsled racing). Butcher twice finished in second place (1982, 1984). She began the 1985 race with a solid lead but was eliminated from the competition when a moose charged across her path, killing 2 of her dogs and wounding 13. That year Butcher lost to Libby Riddles her chance to become the first woman to win the Iditarod. The following year, however, Butcher came in first with a record-breaking time of 11 days, 15 hours, and 6 minutes. She was victorious in both 1987 and 1988 to become the only musher in the history of the sport to win the Iditarod in three consecutive years. She won for a fourth time in 1990.

Butcher retired from competitive sledding in 1994 and opened a kennel in Eureka, Alaska, where she housed more than 150 huskies and trained dogs year-round. She was considered by many to be one of the strongest and most disciplined female athletes of the 20th century for her determination to rise to the top of a physically grueling sport that is dominated by men. In 2006 Butcher died of leukemia.