In his first outing as a declared presidential candidate, Republican Mitt Romney continued his assault on President Obama here Friday, using new unemployment data to claim that Obama’s policies have only deepened the nation’s economic downturn.

“What he did simply was wrong,” Romney said during a town-hall meeting. “On almost every dimension, what he did did not help the economy get out of the slide it was in, but instead he extended the downturn and made it deeper.”

The former Massachusetts governor, pitching himself as a candidate with the business know-how to turn around the economy, added: “The Obama prescription for the economy didn’t ail what hurt us. Instead it made things worse. And I believe it’s time for someone who’s actually had a job do the job of getting jobs for the American people.”

A day after officially launching his second presidential campaign, Romney sought to place blame for the country’s 9.1 percent unemployment, home foreclosures and growing debt squarely on Obama.

“Look, he’s a nice guy,” Romney said. “He’s well spoken. He can talk a dog off a meat wagon. And yet he hasn’t delivered. . . . He can’t keep blaming George Bush. This is now his economy, and what he has done has failed the American people. And the borrowing and the spending and the $1.6 trillion deficit — these numbers are his, they’re on his back, and it’s why he’s going to lose.”

Romney’s town hall began as Sarah Palin was finishing breakfast with Sen. Kelly Ayotte (R-N.H.) at the Golden Egg Diner in nearby Portsmouth. The former Alaska governor’s trip through the Granite State trumped Romney’s on the front page of Friday’s Manchester Union Leader. The newspaper trumpeted her visit with a big headline — “Palin hits the Seacoast” — and relegated a story of Romney’s announcement to Page A3.

Before leaving the state, Palin said she not only plans to visit the key early caucus state of Iowa on one of her upcoming bus tours but also South Carolina, another early primary state. But she offered no further insight into whether she will be a candidate.

Meanwhile, Romney spoke for about 45 minutes in a lecture hall at the University of New Hampshire at Manchester, addressing an array of issues in answers to about eight questions from the audience.

On spending, Romney said there are worthy domestic programs that the country can no longer afford, but he did not delineate which ones he would cut or eliminate.

Addressing the defense budget, he acknowledged that “there’s a lot of waste” in the Pentagon, but said any savings obtained through efficiencies at the Department of Defense should be used to rebuild aging systems. He said the government should use that money to modernize the Navy and Air Force, increase the number of soldiers in the Army and improve care for veterans.

Romney said more substantial savings should be found in mandatory entitlement programs, such as Medicare and Medicaid. Asked about Medicaid, a program that provides health care for the poor, Romney said: “I would send [it] back to the states. I would let the states care for their own poor and their own uninsured in the way that they think is best.”

That approach is similar to the one outlined in the GOP budget proposal sponsored by Rep. Paul Ryan (R-Wis.). But Romney said that on Medicare, the government insurance program for seniors, he would have a different plan than Ryan’s, although he offered few details.

“No one in my party has proposed any change for those programs for anybody who’s retired or who’s near retirement,” Romney said. “The question is, what are we going to promise people in their 20s, 30s and 40s? And the answer is, let’s tell them the truth.”

Romney only briefly addressed Obama’s health-care overhaul law or the similar Massachusetts plan he signed as governor that is a liability in his campaign, restating his desire to repeal the new law signed by the president in 2009.

But when asked about the new federal law’s coming guarantee that people with preexisting conditions cannot be denied coverage, he said that was one area where the federal government should play a role.

“There are some things I want to make sure we do at the federal level, and one is relating to preexisting conditions,” he said. “I would propose at the federal level we say that, if an individual had been continuously covered for some period of time, that they can’t be denied ongoing coverage because they developed what’s known as a preexisting condition. That’s something I say is just fair in dealing with insurance.”

Fielding his first question, Romney was asked whether he believed the science that suggests global warming. He said he did. “I believe the world’s getting warmer,” Romney said. “I can’t prove that, but I believe based on what I read that the world’s getting warmer, and I believe that humans contribute to that.”

Romney dismissed a cap-and-trade policy, saying it would put American companies at a competitive disadvantage in the world. Any solution, he said, would have to be international in scope. “We don’t call it America warming,” he said. “We call it global warming.”

Romney added that, if elected, he would encourage more domestic oil drilling and spur the development of alternative energy sources, such as natural gas and nuclear energy.

“We can’t just say it’s going to be all solar and wind,” Romney said. “I love solar and wind. But they don’t drive cars. And we’re not going to all drive Chevy Volts.”

For the second day in a row, Romney’s wife, Ann, introduced him to a New Hampshire audience. “We’re in it to win it,” Ann Romney declared. She said the 2008 campaign was a “tough process,” but that she had “pushed Mitt into this” a second time because she worries about the future their grandchildren might face.

“Sweetie,” she told her husband, “it’s up to you.”