For Massachusetts Gov. Mitt Romney today responded head-on to critics who say he flip-flops on issues, telling a crowd at a New Hampshire town hall that “it’s not that every single issue I’ve looked at my entire life I’ve never changed my view on.”

While Romney never mentioned chief rival Texas Gov. Rick Perry by name, he certainly seemed to be referencing him in answering a question from a voter asking how to respond to those who question Romney’s candidacy.

Romney at first joked, “Let me give you some brass knuckles, that should help.”

But then he launched into a more serious answer, taking what sounded like veiled swipes at Perry.

“The nature of politics is that you try and find some edge to characterize your opponent and beat him over the head, and that is if you don’t have a optimistic or positive message of your own,” said Romney.

“That’s going to happen and I understand it,” he said. “It’s pretty rough and tumble and I don’t whine about that I realized that when I got into [politics].”

Then, without specifically mentioning Perry’s latest web video attack on Romney, which accuses him of switching his stance on Obama’s stimulus plan, Romney said, “The nice thing about writing a book is that you can read it and see what I stand for.”

“In the private sector, if you don’t change your view when the facts change, you’ll get fired for being stupid,” Romney added.

Romney also questioned whether President Obama’s chief campaign strategist had ever seen the movie “Titanic,” linking a comment from David Axelrod about the struggles of the Obama campaign to the infamous ship that sank and killed more than 1,500 people.

“[David Axelrod] said that the Obama campaign was going to be a ‘titanic struggle,’” said Romney. “I’m not sure he knows what that word means, I’m not sure he saw the movie.”

Romney held a town hall today at St. Anselm College in Goffstown, N.H., in the exact same room Axelrod spoke on Tuesday. This is Romney’s eleventh town hall since announcing his presidential campaign in June, and today he spoke in front of a replica of the debt clock, which ticked behind him as he spoke.

The former Massachusetts governor couldn’t stop himself from ribbing Axelrod for his comments, saying that comparing the campaign to a devastating ship wreck couldn’t be more appropriate.

“It’s true for a lot of reasons,” said Romney. “The captain of the ship has been inattentive, otherwise occupied or asleep for most of the voyage.”

“[The ship] is going to sink,” he added, to the roar of the more than 200 people packed in the college seminar room.

In a lighter moment during the town hall, Romney called on two young girls to ask questions. One asked if Obama would raise babysitting taxes and the other asked what advice Romney would give to kids to encourage them to go into politics.

Romney didn’t miss a beat — joking that the answer about getting into politics is “don’t do it.” As for the babysitting taxes, Romney told the fifth grader, “You’re probably OK. But if you’re a professional babysitter, you better watch out.”