CONCORD, N.H. — Senator Clinton spent her first day in New Hampshire in over a decade fending off confrontational questions about her position on Iraq and passed on another opportunity to denounce her vote for the war as a mistake.

In the gymnasium of Concord High School in this capital city, a software engineer, Dave Tiffany, condemned the junior senator for her 2002 vote to authorize President Bush to got to war saying, “You seem to want to have it both ways.”

“You said that you are opposed to surge, but yet you won’t use power of the purse,” said Mr. Tiffany, who spoke from the gym bleachers. “As we’ve heard today you say your vote for the resolution authorizing President Bush to go to war was a vote for continuing the UN inspections. You seem to want to have it both ways.”

Mrs. Clinton — who made her appearances the same day Senator Obama, Democrat of Illinois, officially kicked off his presidential campaign — had moments said earlier she never would have started the war if she had been president and that she will end it in 2009 if elected. She then said it is “very easy to go around saying end the war now.” That is exactly what her Democratic rivals John Edwards and Mr. Obama are doing.

“We are working to try and change the president’s policies. I know there is a great deal of frustration and anger and outrage that we can’t just wave a magic wand and make things change,” she told the crowd of about 2,000 people, in the same room that has hosted a long line of presidential candidates, including her husband.

She explained that in the Senate you have to get 60 votes to “do anything.” “Well, finally we have a Democratic president, I mean a Democratic Congress,” she said in a slip before quickly adding, “If we had a Democratic president we would end the war.”

While the subject of Iraq was only one of dozens of topics Mrs. Clinton addressed yesterday, the audience’s questions made it clear that it could be the Achilles’ heel in an otherwise well-oiled and well-financed campaign operation.

At another “town-hall” event in Berlin earlier in the day, a questioner, Roger Tilton, demanded that she acknowledge that her vote for the war was a mistake — a step Mr. Edwards has already taken.

“I want to know if right here, right now, once and for all and without nuance, you can say that war authorization was a mistake,” Mr. Tilton said, according to the Associated Press. “I, and I think a lot of other primary voters — until we hear you say it, we’re not going to hear all the other great things you are saying.”

Mrs. Clinton did not denounce her vote. Instead, she said, as she has in the past: “Knowing what we know now, I would never have voted for it.”

“The mistakes were made by this president who misled this country and this Congress,” Mrs. Clinton said, according the AP.

Despite having to defend her positions on the war, Mrs. Clinton was largely a hit with the audience and was interrupted several times with the kind of standing ovations she might have gotten if she has slam dunked a basket and won a championship basketball game for the school. She is leading her Democratic opponents here by wide margins.

Mrs. Clinton spent most of her time talking about topics other than the Iraq war — such as her views on everything from CEO pay, which she called “outrageous,” to energy dependency, universal health care coverage, and other issues meant to appeal to middle-income Americans.

As she did during back-to-back stops in Iowa, Mrs. Clinton was also quick with jokes and seemed to easily harness all of the energy in the room.

She noted that she was a Girl Scout as a child, but then joked that she wouldn’t be singing the Girl Scout song about making new friends – a motto for her in New Hampshire – after an unflattering video of her singing the Star-Spangled Banner hit the Web Site YouTube a few weeks ago.

She also recalled campaigning with President Clinton when he was on the stump in 1992 and 1996 in New Hampshire. “I’m going to make one change from my husband’s campaign, and I want all of you to help me keep to this. Not so many Dunkin’ Donuts stops. I can’t afford that,” she said to laughter.

Mrs. Clinton has several house parties with Democratic activists and another town hall event in Keene, New Hampshire, tomorrow.