MANCHESTER, N.H. — To judge from one gathering of swing-state voters, for all the fireworks at Wednesday night’s first presidential debate in Colorado, neither candidate changed many minds.

“They’ve both done a good job defending their positions,” said Ian Norton, 18, a Saint Anselm College student from Kingston, N.H., who said he was casting his first presidential ballot for Mitt Romney before the debate and still planned to afterward.

“Obama has had four years to fix the economy. His policies haven’t worked,” Norton said.

Norton was one of about 50 voters — most already in one candidate’s corner, but a handful still undecided — who attended a debate-watch party at Saint Anselm, in the heart of a key battleground state. None of those interviewed beforehand had shifted their stance after the debate, although several undecided voters said they at least had a better opinion of one or both of the candidates afterward.

Joe Donahue, 21, a Saint Anselm senior originally from Auburn, Mass., said before the debate that he was leaning toward Obama, in part because he did not think Romney had been a good Massachusetts governor.

‘It was a good discussion. I just don’t think I learned anything new.’

“He said he wouldn’t raise taxes but he raised every fee possible,” Donahue said.

As the debate wrapped up, Donahue credited Romney for being aggressive. Still, Donahue said he wasn’t satisfied with the former governor’s explanation of how he would cut the deficit without raising taxes and didn’t like the Medicare stance Romney outlined. He was still leaning toward Obama.

“I think he’s really trying to make a difference,” Donahue said of Obama. Romney, he said, was “not as tuned in with what’s going on with Americans. The whole 47 percent thing made him sound pretty ignorant.”

Joan Connacher, 71, a retired nurse in Nashua who has volunteered for the Obama campaign, said she thought both candidates had done well but that she was sticking with the president.

“I didn’t think Romney hit it out of the park like he was supposed to,” she said.

Griffin Roberge, 19, originally from South Berwick, Maine, who was also leaning toward Obama going in, said he felt Romney turned in a good performance that gave him pause.

“I was leaning toward Obama going in,” Roberge said. “I felt like Romney answered the questions very well.”

But he wanted to watch the next two debates before making up his mind. “I’m still undecided,’’ he said.

Another undecided voter, Kevin Staley, 54, a philosophy professor at Saint Anselm who lives in Manchester, said before the debate that he was sick of all the candidates’ attack ads and hoped to get “a view of their character and soul” in the debate.

“I’m enervated by all the negative campaigning. If I believed all the ads, I’d vote for no one,” he said. “I’m looking for a reason to vote.”

Afterward, he said he thought it was impossible to judge the flurry of factual assertions and counterassertions both candidates offered, but was impressed by the tenor of the debate.

“It was good to see two individuals speaking civilly to each other,” he said.

However, Staley said he remains undecided.

“It was a good discussion,” he said. “I just don’t think I learned anything new.”