Mackey registered the win after mushing 1,110 miles, surpassing both Doug Swingley, who had won three straight Iditarods from 1999-2001, and Susan Butcher (1986-88) to become the winningest racer ever.
The native of Fairbanks, Alaska, finished 90 minutes ahead of his closest pursuer, Hans Gatt. Mackey rested for only 4 minutes before leaving the final checkpoint and setting out on the final 22-mile leg into Nome.
Only Gatt and Jeff King had left the final checkpoint at the time of Mackey's finish out of the remaining 57 mushers.
Mackey's father, Dick, won the Iditarod in 1978 and his older brother, Rick, captured the 1983 race.
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