Dick's other son, Lance Mackey, won four consecutive Iditarods in 2007, 2008, 2009 and 2010, thus becoming the second legacy winner.
In 1978, Mackey pulled ahead of Rick Swenson during the last leg of the race from Point Safety to Nome.
With less than 10 miles (16 km) to go, Mackey had a 2-mile (3-km) lead, but by the time he reached the chute to the finish line along Front Street in Nome, they were neck-and-neck.
Swenson initially believed he had won, and when he learned otherwise he told Gavin, "if you made a decision, stick by it".
134) Mackey's winning time was 14 days, 18 hours, 52 minutes, and 24 seconds, and his lead dogs were named Skipper and Shrew.