The official start of the 1,100-mile race from Anchorage to Nome was moved about 25 miles north this year because of too much ice on a trail closer to Anchorage that is normally used.
"I don't think it is any harder than I imagined. It's hard," said Todd Capistrant, a physician from Healy who didn't finish last year but is determined to do so in 2004. "You find out what's inside. It tells you who you are."
The Iditarod, now in its 32nd year, commemorates a 674-mile relay race from Nenana to Nome in February 1925, when dog teams successfully delivered serum to prevent an outbreak of diphtheria among children.
A record 87 teams - that's about 1,440 dogs - are competing for prizes which this year total over $700,000. The winner receives $69,000 and a new pickup truck worth more than $41,000.
The race is not without its critics, including most notably People for the Ethical Treatment of Animals. PETA says that in contrast to the lifesaving purpose of the relay in 1925, Iditarod dogs are unnecessarily subjected to cruel conditions - including running for hours with little rest, in harsh and at times dangerous weather - which in some cases can lead to death.
Aficionados of dog sledding say the dogs love the race and are not mistreated. They furthermore point to the Iditarod as a way to preserve a tradition which had a historic role in the development of Alaska - one that did not begin to fade until the 1960s, with the advent of the snowmobile.
The Iditarod organization, on its web site, stresses the veterinary care dogs get before the race and at various checkpoints during the competition. It also says sled dogs are exposed to environmental and athletic factors most dogs will never encounter.
In the Iditarod, it normally takes the top dog sled teams nine to 10 days to reach Nome. Four-time champion Martin Buser and his team hold the course record of eight days, 22 hours, 46 minutes, set in 2002.
Buser, who came in fourth last year and won in 2002, said he feels better than ever this year.
"I'm just getting good," he said.
Like all top athletes, Buser has fans.
Suzanne Jammin came all the way from Washington, D.C., to stand next to four-time Iditarod winner Martin Buser of Big Lake and get a photograph with him before the start. Buser is running in his 21st Iditarod.
"We have followed him since the beginning," said Jammin, who recently moved from Alaska and admits she is a bit homesick.
Jammin was among the crowd of dogsled fans who lined up three-deep Saturday at the starting line of the race, to get autographs, pose for pictures with their favorites - human and canine, and above all, cheer them on.
Nancy Jostad of Hoboken, N.J., came to Alaska especially for the start of the race. She waited in line to have her picture taken with Aliy Zirkle of Two Rivers, one of 17 female racers in the 2004 field.
"I'm so excited," Jostad said. "Women rock."
The ceremonial start of the race is held each year on the first Saturday in March. But the serious racing began Sunday.
Iditarod veteran Vern Halter, of Willow, was the first to shove off in the staggered start. He gave each of his 16 dogs a reassuring pat and a quick wave to a crowd of spectators.
Halter, a 53-year-old lawyer and full-time kennel owner, is in his 16th Iditarod. His best finish was in 1999, when he took third. He has finished in the top 10 six times, earning placement in the first position.
"I like that position," Halter said. "If you're going to be in the top 10, you might as well be first."
Mushers say the race is a true test for the dogs and the musher on the sled. Not only is the race expensive - by most accounts it costs at least $20,000 to field a team - but much time is required to train.
Teams from nine states and Canada, Italy, Germany and Norway are competing.
Last year's winner, Robert Sorlie of Norway, is not racing.
But there are other comers in the field, for those who follow these things.
Ramy Brooks of Healy, who came in second in 2002 and 2003, is hoping to emerge as champion this time around.
"I'm shooting for that first win," Brooks said, wearing a teal-green mushing suit with yellow and orange flames up the sleeve.
Jeff King, who has won the Iditarod three times, was confident going into this year's race, and scoffed at Buser's dog team - which Buser calls "quiet, confident, even, deep and balanced."
King says he's seen Buser's canine team before and he wasn't impressed.
Four-time winner Doug Swingley of Lincoln, Mont., is back after taking last year off. Both Swingley and Buser have their eye on Rick Swenson and would like to catch up with his status as the Iditarod's only five-time winner.
Swenson, who hasn't won since 1991, said he's gone back to basics this year, focusing less on himself and more on the dogs.
"I've tried every gimmick in the world to win this," Swenson said. "The most important thing is in front of the sled."