Update: Four mushers had reached Takotna by 2:30 a.m. led by Lance Mackey who arrived just before 2. Within about half an hour, Kjetil Backen, Jeff King and Paul Gebhardt had joined him in the small checkpoint, 18 miles from McGrath. Three more were on the trail to Takotna by 3:30 a.m., including Jim Lanier, Aaron Burmeister and Sebastian Schnuelle. They were followed around 4 a.m. by Jessie Royer and Sigrid Ekran.

---

Despite unusually warm temperatures in the upper Kuskokwim River valley, defending Iditarod Sled Dog Race champion Lance Mackey from Fairbanks vaulted to the front of the race Tuesday afternoon.

As other teams rested in the peaceful Interior village of Nikolai, Mackey got his team up and on the trail to McGrath after a rest of less than five hours.

The move put him in the lead, but the rest time in the village was somewhat deceptive. A satellite tracking device on Mackey's sled stopped moving in the Farewell Burn early Tuesday morning, indicating he and the dogs had taken a long break there.

With temperatures pushing into the mid-30s, four-time champ Martin Buser appeared to be taking an even longer one. The satellite showed him and his dog team camped out on the Salmon River about 10 miles from Nikolai. There is an old fish camp there, and it has long been a favored stopping place for the musher from Big Lake.

More than a dozen teams passed Buser and his dogs as they rested, but the Buser crew was back on the trail by evening. They blew right through Nikolai and joined a pack chasing Mackey and four-time champ Jeff King from Denali Park.

The methodical King gave his team a full five hours in Nikolai before pulling out 30 minutes behind Mackey. The GPS tracker showed him catching and passing Mackey as the race moved west down the frozen Kuskokwim River and the riverside swamps on its way toward McGrath.

The river between that transportation hub and the Native village back down the trail is serpentine. The winter snowmobile trail mushers follow jumps overland in many places, at times running straight as an airport runway for miles across grass swamps turned into huge fields of white by winter snows.

Mushers get a good chance to size each other up there.

Mackey, no doubt, got a good look at King's team when he passed. Norwegian Kjetil Backen and 2004 champion Mitch Seavey would offer a different view when they passed later on.

Backen led the race into Nikolai and has been forging the pace much of the early going, as has been the style of the Norwegians frontrunners in past Iditarods. Backen training partner and friend Robert Sorlie, a two-time winner, holds the best winning-percentage in Iditarod history. And Backen has finished as high as third.

He is clearly in the hunt again this year, but the field is a tough one.

Mackey, the defending champ, has been on a roll since winning the 1,000-mile Yukon Quest International Sled Dog Race in 2007. He followed that up with his first Iditarod victory and a successful defense of his Quest crown last month.

King, who last won in 2006, wants badly to get back in the winner's circle.

Paul Gebhardt from Kasilof, the runner-up last year, believes he could have won last year, and he's out to prove it.

Buser, the race record holder and the least consistent performer among the former champs -- he can finish anywhere from first to 21st -- has what appears to be the fastest team on the trail. They've regularly posted speeds up around 11.5 mph between checkpoints while most teams have been lucky to get over 10 mph.

And lastly, there's 55-year-old Rick Swenson from Two Rivers, the only five-time winner in race history. He's a musher looking to prove wrong those who have noted his recent 25th and 26th place finishes and suggested he might be over the hill. Swenson has run with the leaders in this race, a somewhat unusual position for a musher who likes to make a charge from behind.

But then the Iditarod has changed much since he and the late Susan Butcher, another four-time champ, owned it in the 1970s and 1980s.

Back in those days, the slow and steady tortoises always caught the speedy hares.

Today, however, there are so many rabbits, and so many have become masters at building endurance into their dog teams, they can't be allowed to run free. If they get a gap on the rest of the field, one of them will win even if others wilt.

As the 2008 race moves at quick pace toward the point where teams typically take their one mandatory 24-hour rest -- usually just before, at or just past halfway -- the question of who has the most endurance looms large.

A quick early pace may have been enough to run some of the speed out of the fastest teams.

Buser isn't the only one back there with fast dogs. He, Swenson, Backen, Gebhardt, former Quest champions Aliy Zirkle from Fairbanks and Hans Gatt from Whitehorse, Yukon Territory, along with Iditarod veteran Jason Barron from Lincoln, Mont., all appear to have good team speed.

And then, some mushers are masters at hiding what they've really got. King reported hauling a couple dogs in his sled to slow his team on the run up the Yentna River to Skwentna. Freighting that load is one way to hide some speed, and to keep some dogs fresh for late in the race when foot speed really begins to matter.

---

Find Craig Medred online at adn.com/contact/cmedred or call 257-4588.

---

Garnie scratches in Rainy Pass

• Veteran Joe Garnie of Teller scratched Tuesday morning at Rainy Pass, citing health issues with his team which was having trouble adjusting to the warm weather. Garnie had 13 dogs left when he scratched. Garnie was the runner-up in the 1986 Iditarod.

• Tom Roig of Shreve, Ohio, scratched at Finger Lake Tuesday morning. The 57-year-old rookie from Shreve Ohio cited health issues with himself and his team. TALKEETNA -- Norway's Kjetil Backen was the first musher to reach the checkpoint at Nikolai, checking in at 10:39 a.m. with 15 dogs.

Backen, of Porsbrunn, Norway, coasted into the checkpoint, 401 miles into the 1,100-mile race. Told he was in the lead, he said, "I can see that."

Backen told onlookers the going was rough on the frozen Kuskokwim River.

"I fall over but it's all right," he said. "No problem."

Veteran Gerry Willomitzer of Whitehorse, Yukon, was second in to Nikolai, population 109, the first of many Native villages along trail to Nome. Willomitzer, a veteran Yukon Quest International Sled Dog Race, clocked in at 11:17 a.m. with 14 dogs.

Race organizers said unusually high temperatures along the early stretch of the trail are the main concern in the Iditarod so far.

Race spokesman Chas St. George said some areas were reporting temperatures in the 30s, which "is too hot for the dogs to run in." A stretch between the checkpoint at Rainy Pass and Nikolai reported a high of 43, according to the National Weather Service.

St. George said last year about this time, temperatures were in the zero degree range in this part of the trail.

At the same time, teams are dealing with heavy snow all along the trail.

"But there are no blizzard conditions," St. George said, "Everybody's moving."

About 20 dogs have been dropped so far, but there are no serious casualties, according to St. George. He said the numbers were tapering off.

"Usually in the first third of the race, mushers expect to drop a lot of dogs. This is an area for a lot of opportunities for sprains or other injuries."

Two mushers scratched Tuesday. Tom Roig of Shreve, Ohio, dropped out, citing concern for his health and the health of his team. Joe Garnie of Teller also quit, citing health issues with his dog team. A record field of 93 mushers remains in the running.

Until mushers begin taking a mandatory 24-hour layover and two 8-hour rests, the race is fluid.

In its 36th running, the race commemorates a run by sled dogs in 1925 to deliver lifesaving diphtheria serum to Nome.

The modern-day Iditarod trail crosses frozen rivers, dense woods and two mountain ranges, then goes along the dangerous sea ice up the Bering Sea shore to the finish line under Nome's burled arch. Along the way, mushers can encounter temperatures far below zero, blinding winds and long stretches of frigid overflow.