FAIRFIELD, Iowa – Two Democratic front-runners came within 100 miles of each other this week in a long, hot day of Iowa barnstorming.

But in the eyes of some supporters - not to mention national observers - Sen. Hillary Rodham Clinton and Sen. Barack Obama often seem even further apart.

At nationally televised debates, they're cordial to each other.

But they have a lingering disagreement about the way the country got into the unpopular war in Iraq. Their fans and surrogates are pointing fingers on the Internet, and their efforts to raise campaign cash are becoming another closely watched contest.

As the candidates came close to crossing paths in eastern Iowa Tuesday, some undecided Democrats in the crowds said they hoped the rivalry would not intensify between now and January, when the first votes are cast at Iowa caucuses.

"I'm really torn between Obama and Hillary," said John Christenson, 70, a retired library director who caught Clinton's midday rally at the University of Iowa in Iowa City. "I've heard both of them talk, and I haven't disagreed with a thing anyone said." "I'd rather see some collaboration," said Ryan O'Leary, 30, of -Iowa City. "I do care, because I think both of them have the ability to inspire people."

Clinton continued her "Billary" tour, introducing crowds in both Iowa City and Davenport to a man who could become the nation's first "First Gentleman," former President Clinton.

Meanwhile, Obama was just to the south, stumping in Keokuk, Mount Pleasant and Fairfield, with three more Fourth of July events on tap Wednesday.

In Fairfield, a couple of thousand gathered around the town gazebo to hear Obama make his stump speech calling Iowa "ground zero of the politics of hope."

He hit on all the Democratic topics like stopping the war, making the country energy independent and providing universal health care. But he argued that details of the candidates' various plans aren't as important as the leadership question.

The crowd cheered, and on the edge of the square, a car horn honked. It was a Republican couple, Jack and Shirley Cavenee. They weren't honking their approval but were trying to get the attention of a hat salesman so they could buy an Obama baseball cap. "I like what this guy says," said Jack Cavenee, 75, who planned to vote for a Democrat for the first time since John F. Kennedy in 1960 - but only if the nominee is Obama, not Clinton.

"Every time I've heard her speak, I did not feel she was sincere," Shirley Cavenee said.

Although Clinton leads the national polls, with Obama second, neither tops polls in Iowa. The front-runner here is former Sen. John Edwards of North Carolina, who decided not to join the fight for media attention here this week.

The war remains a dividing point between Clinton and Obama. While she was among those who voted for a war powers resolution in late 2002, giving President Bush congressional authority to confront Iraq, she has been reluctant to say she made a "mistake" - as others, including Edwards, have done.

Obama was not in the Senate at the time, and at every opportunity he has pointed to his statements opposing the war.

At Clinton's appearance with her husband Tuesday in Iowa City, local resident Jim Walters stood on a nearby bridge holding a sign above his head saying: "Hillary voted for this war."

It drew the attention of news photographers and, according to three witnesses, prompted Clinton supporters to call for security and attempt to block his sign with Hillary for President placards.

That outraged some undecided voters like Nick Kowalczyk, 27, a University of Iowa graduate student. So he and some friends took some other signs Walters had with him and held them over their heads.

Afterward, Kowalczyk said he hasn't made up his mind yet, but he wants Clinton and Obama supporters to keep their disagreements civil because they might make a good ticket some day.

"I am leaning toward Obama, but I wanted to hear her," Kowalczyk said. "If they were a ticket together, that would be nice."

But that means the two camps need to play nice.

"One thing I don't like about Hillary is her establishment status. But it means she knows how to get things done," Kowalczyk said. Meanwhile, Obama is a relative newcomer - "inexperienced" - various Clinton backers are quick to argue. But that might make them complementary, Kowalczyk said.

At an event Monday night in Des Moines, where former President Clinton was making his first campaign rally appearance alongside his wife, many of her backers also liked Obama.

"I just want anyone who's not male and white," said Bill Boon, a retired college professor who is both male and white - except for the red clown nose he was wearing. "White males are what I don't want anymore."

Why not put them on the same ticket, said Evelyn Buddin, 87, of -Iowa City, sitting in the shade as the Clinton event was clearing out.

Buddin was born in 1920, the same year women were able to vote in national elections for the first time. She has been hoping for a female president since the 1950s. She's rooting for Clinton. But she doesn't see why she and Obama couldn't be on the same ticket.

"Each one would have to give a little," Buddin said. "I think they can work it out."