The Democratic presidential nominating race appears to be tightening in Iowa, with former Sen. John Edwards barely clinging to a fractional lead over Sen. Hillary Rodham Clinton, according to the latest campaign polls.
With six months before the primary contests begin, Mrs. Clinton also holding solid leads in the early states of Nevada, New Hampshire, South Carolina and Florida, strengthening her position as the party's front-runner.
But Iowa, the nation's first nominating battleground on Jan. 14, retains its political importance as the place where a victory can give a candidate critically needed momentum heading into later contests. That is where Mrs. Clinton, of New York, hopes to overtake Mr. Edwards, the party's 2004 vice-presidential nominee.
The former senator from North Carolina was leading there last week by an average of 0.6 percent, according to Real Clear Politics, a Web site that tracks candidates and calculates a running average of the most recent polls. Mr. Edwards led by a larger margin last month, but the average fell sharply last week after an American Research Group poll conducted at the end of June showed Mrs. Clinton inching ahead of him, 32 percent to 29 percent.
"I'm not sure we're seeing a trend there yet. Folks I talk to on the ground in Iowa tell me that Edwards still has to be considered in the lead in Iowa. That's what the private polls are telling us," independent pollster John Zogby said.
"Still, it is very competitive in Iowa. No one has a commanding lead," Mr. Zogby said Friday.
The American Research Group poll showing Mrs. Clinton moving into the lead in Iowa was released shortly before she and her husband, former President Bill Clinton, conducted a July Fourth campaign swing through the state in a move to boost her poll numbers.
"Certainly that was indicative of their desire to use Bill Clinton early, as opposed to trying to strengthen her position later in the campaign," Mr. Zogby said. "That suggests to me that they're worried. Generally, you pull out your trump card when you are feeling vulnerability from the other side.
"So you have Edwards leading in Iowa and Senator Barack Obama leading in fundraising and it's time to get really serious and make your moves to get into the lead," he said.
But if Mrs. Clinton is struggling to carve a clear lead in Iowa, she is dominating her rivals just about everywhere else.
In New Hampshire, an American Research Group poll showed her leading the Democratic pack with 34 percent. Mr. Obama of Illinois was in second place at 25 percent and Mr. Edwards was a distant third at 11 percent.
In Florida, Real Clear Politics showed Mrs. Clinton, polling a hefty 38 percent support among Democrats, racing ahead of her nearest rival, Mr. Obama, by an average of 16 points.
In South Carolina, she led with 37 percent, and was crushing her rivals in Nevada in every poll taken in the past several months, drawing up to 40 percent support from Democrats at the end of June.
She was similarly running ahead of her rivals throughout the Midwest and Northeast, according to Real Clear Politics, leading Mr. Obama by 38 percent to 25 percent in Michigan and by 39.3 percent to 20 percent in New Jersey.