Five mushers have scratched. A sixth, Canadian Gerry Willomitzer, was withdrawn Sunday after losing a dog that was later found.
The first musher to reach Nome will win $50,400 and a new 2013 Dodge Ram pickup truck. The rest of the $600,000 purse will be split among the next 29 mushers to cross the finish line.
As teams push toward Nome, the town of 3,700 was bustling with anticipation.
Volunteers in the old gold rush town erected the famed burled arch on Front Street, a block off the sea, on Sunday. Monday morning, volunteers put up the finish banner that hangs above the arch.
Inside the city's small convention center, which doubles as race headquarters, banners with each musher's name were being hung from the rafters by volunteers working with Alaska Missions including Shannon Scoggins, 22, of Stephenville, Texas.
Her group will spend the rest of the week caring for the canine participants at dog lots on the outskirts of town.
"It'll be a once-in-a-lifetime chance," she said. "We're excited about that."
In Nome, McLarnon said the race was shaping up to have an exciting finish with so many front-runners clustered together.
But will it match the 1978 mad dash down Front Street that left Dick Mackey as the winner with one second to spare over Rick Swenson, who went on to become the Iditarod's only five-time champion?
"You know, it very well could be" McLarnon said. "The way the things are looking right now, it could be one of those close ones."
Race watchers are predicting a Tuesday afternoon finish in Nome, but off any record-setting pace. McLarnon said it usually takes mushers about 18 hours to reach Front Street after they hit White Mountain, a checkpoint 77 miles from the finish and where they have to take a mandatory eight-hour layover.
"In that last 77 miles, anything can happen," McLarnon said.
Associated Press writer Rachel D'Oro reported from Anchorage. Follow her on Twitter at https://twitter.com/rdoro .