Edwards was the first to name campaign chairmen in all 99 Iowa counties, and he has precinct captains in nearly 90 percent of the state's 1,784 precinct.
The size of the crowd doesn't rule at the Iowa caucuses:
....Because of the unusual system of counting votes and assigning delegates, candidates can't "run up the score" by drawing huge crowds to urban precincts while leaving other areas of the state untouched. In some tiny precincts, a candidate can win delegates even if just a handful of supporters show up.
A big factor is going to be the candidates who won't win 15% of the vote at a caucus -- Biden, Richardson, Dodd, Kucinich. They get to direct their supporters to one of the top tier.
The Boston Globe explains how coming in second in Iowa could lead to a winning hand.
The supporters of candidates who don't reach the benchmark have several choices, including going home. But what often happens is this: Those candidates' supporters line up behind other candidates who are viable, adding to their strength and increasing their chances of winning that particular caucus. Thus winning is about not just being many voters' first choice, but many voters' second.
"In this race, especially since it is so close among the top three, where the second-choice folks decide to go is going to be absolutely critical, and in fact could determine the difference," said Matt Paul, who was Howard Dean's deputy Iowa director in 2004.
So where will the supporters of the second tier candidates go....to Hillary, Obama or Edwards? If it's Edwards, he's still very much in the race.
Update: The WSJ also has an in-depth article on Edwards, saying it's still a three way race and if he comes in first or second in Iowa, it could shake up the states that follow.
Among the top Democrats, Mr. Edwards still stands the longest odds. His national organization is substantially smaller than those of rivals. He doesn't lead in polling in any state that has been surveyed. He has a small fraction of the money of his chief rivals. He lacks the establishment imprimatur that gooses the campaigns of Mrs. Clinton and even Mr. Obama.
But Mr. Edwards has spent six years of working the farms and small towns of Iowa -- a virtually uninterrupted string of campaigning that started when he began running for president in 2002. He has a bank of seasoned supporters that polls consistently show are more likely to turn out on caucus night, even if the weather is poor.