TAKOTNA, Alaska — Former champion Mitch Seavey took the lead at the Iditarod Trail Sled Dog Race on Wednesday, the first musher to reach the ghost town of Ophir.

The winner of the 2004 race overtook the earlier leaders, including defending champion Lance Mackey of Fairbanks, by staying only two minutes at the Takotna checkpoint.

Seavey covered the 25 miles to Ophir — 444 miles into the 1,100-mile race — in just under three hours.

Also out of Takotna were Hugh Neff of Skagway, Zack Steer of Sheep Mountain, Ed Iten of Kotzebue, Paul Gebhart of Kasilof, Ramey Smyth of Willow and Martin Buser of Big Lake.

Besides Mackey, 11 other mushers remained at Takotna early Wednesday.

The 37-year-old Mackey was the first to reach the Takotna checkpoint.

Mackey, who last year became the first to record back-to-back wins in the 1,100-mile Yukon Quest International Sled Dog Race and Iditarod, rested his team for nearly five hours in Nikolai on Tuesday before getting back on the trail to Nome.

"I do the best I can with what I have in front of me," Mackey said last week about his race strategy. "I expect the worst and hope for the best."

Race organizers said 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 Tuesday, 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 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."

Race officials said neurosurgeon Cliff Roberson of Corvallis, Ore., scratched Wednesday morning at the Rohn checkpoint after suffering minor eye injuries. Roberson, the fourth to scratch, ran the race several times in the early 1990s, and his entry this year was a 60th birthday gift from his wife. A record field of 92 mushers remain 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 shore to the finish line under Nome's burled arch. Along the way, mushers can encounter temperatures far below zero, blinding wind and long stretches of frigid overflow.