Concord – Buoyed by the endorsement of Republican U.S. Sen. Judd Gregg, former Massachusetts Gov. Mitt Romney filed today as a candidate in the New Hampshire presidential primary.

Romney, 60, said he expects his campaign, which he said is "growing enormously," to increase its momentum and strength with the boost Gregg's support will give him.

Romney, running as a pro-life conservative, said that as President he will strengthen the military, cut taxes and present balanced budget. He said he favored a tough stance on illegal immigration long before his GOP rival, former Sen. Fred Thompson, brought out a similar plan.

"I think he's a Freddie-come-lately to the immigration issue," Romney said.

As he left a brief meeting with reporters, he said that, "as President I will do everything in my power," to keep Iowa and New Hampshire at the front of the election season calendar.

Romney is the son of former Michigan Gov. George Romney, who ran in the New Hampshire primary 40 years ago.

A Harvard graduate, Romney served one term as governor of Massachusetts. He decided to seek the presidency rather than run for a second four-year term.

Romney worked with the Boston Consulting Group, was CEO of the Bain and Co. management consulting firm in Boston, and co-founder of Bain Capital. He is also former president of the 2002 Olympic Winter Games that were held in Salt Lake City.

Sen. Gregg says he “never thought I’d endorse a governor of Massachusetts for anything, but, I never though the Red Sox would win the World Series twice in my lifetime, either.”

Gregg said he decided to endorse Romney last week after months of consideration.

"We need a can-do problem solver who understands the philosophy of a approaching a problem from a conservative position in Washington," Gregg said.

He said Romney has run a solid traditional New Hampshire primary campaign by meeting with citizens and hearing their concerns and ideas in person.

“We need someone who’s got the vision and optimism to lead the country, someone who understands the key issues we confront, which is the threat of Islamic fundamentalism and ensuring that the Baby Boom generation can retire without going bankrupt,” Gregg said.

He also cited Romney’s “can-do, get-it-done, let’s-solve-the-problem optimism.”

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Gregg said it was a difficult decision because he has “tremendous respect for John McCain and although I don’t know Rudy Giuliani, I respect what he’s done.”

Romney welcomed Gregg to his campaign and told UnionLeader.com it “underscores that I’m a conservative who believes in conservative principles. Am I the most conservative on every issue? Absolutely not. But I’m a conservative who believes in all three pillars of conservatism: social conservatism, economic conservatism and foreign policy conservatism.”

One of Gregg's closest political advisers, Concord attorney Tom Rath, is a high-ranking member of the Romney campaign.

In past primaries, Gregg has endorsed both President George W. Bush and his father.

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