When he was a boy growing up in Norway, he watched videos of the world's most famous sled dog race and figured out a way he could replicate the Iditarod: He borrowed his neighbors' two small house dogs and had them pull him around on skis.
The dogs and equipment got bigger and better until he finally captured the biggest prize in the sport on Wednesday. The 31-year-old became the third person born outside the United States to win the Iditarod Trail Sled Dog Race that spans nearly 1,000 miles (1,609 kilometers) over rugged Alaska terrain.
"I don't know what to say about it. It's out of this world," he said before hugging each of his dogs.
Ulsom came off the Bering Sea ice in the small city of Nome early in the morning and ran his dogs down the last few blocks as a crowd cheered him on. His supporters crowded the finish line, one waving Norway's flag.
His victory generated heavy media attention in Norway, a winter sports nation still basking in the glory of winning the most medals at the Winter Olympics in Pyeongchang, South Korea.
"This is completely insane. It's fantastic to win this race here," Ulsom said, according to Norwegian broadcaster NRK. "It was rather tough. It was hard to keep my tears back when I crossed the finish line."
He picks up about $50,000, a drop from the 2017 winner's earnings of more than $71,000.
The Iditarod, which began March 4, has been suffering financially and lost Wells Fargo bank as a major sponsor in the last year. Organizers have blamed animal rights activists for pressuring sponsors.
The race also was marked by fallout from its first-ever dog doping scandal. Race officials announced that the team of four-time champion Dallas Seavey tested positive for an opioid painkiller after his second-place finish last March but said they could not prove he gave tramadol to his dogs.
Officials didn't punish Seavey but changed race rules to make mushers responsible for any positive drug test. Seavey, who won four titles between 2012 and 2016, denied giving drugs to his dogs and sat out this year's race in protest.
The Iditarod also reprimanded but didn't fire the head of its drug testing program on Monday after a musher claimed Dr. Morrie Craig threatened him minutes before the race's start.
Musher Wade Marrs said Craig threatened to expose him as another musher who had a positive drug test last year. Iditarod spokesman Chas St. George has said Seavey's team had the only positive test.
The Iditarod started north of Anchorage with 67 mushers. Eight of them, including Marrs, dropped out.
Ulsom, the winner, moved in 2011 from Norway to Willow, Alaska, the dog mushing capital of the U.S., after receiving a 10-year sports visa.
He first entered the Iditarod in 2013, when he was named rookie of the year, and has never finished below seventh place. His previous best finishes were fourth-place rankings in both 2017 and 2014.
Ulsom said the last 77 miles (124 kilometers) of this year's race was a "super fun, emotional ride. I'm super happy with the dogs. It couldn't have gone any better."
Associated Press writer Jan M. Olsen in Copenhagen, Denmark contributed to this report.
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