Mitt Romney accepted the Republican nomination for president on Thursday night by asking voters to choose between what he called unfulfilled promises of President Barack Obama and his promise to restore America's greatness.

In the most important political speech of his life, Romney evoked themes and imagery of GOP icon Ronald Reagan in describing to a cheering Republican National Convention a future of opportunity and promise for the nation.

He recalled the excitement of the country in electing Obama four years ago, saying the president's campaign theme of "hope and change" had a powerful appeal.

"But tonight, I'd ask a simple question: If you felt that excitement when you voted for Barack Obama, shouldn't you feel that way now that he's President Obama?" Romney asked. "You know there's something wrong with the kind of job he's done as president when the best feeling you had was the day you voted for him."

Romney said that while his own patriotism caused him to hope Obama would succeed, "his promises gave way to disappointment and division."

"This isn't something we have to accept. Now is the moment when we can do something. With your help we will do something," he said. "Now is the moment when we can stand up and say, 'I'm an American. I make my destiny. And we deserve better! My children deserve better! My family deserves better. My country deserves better!'"

The prime-time, nationally televised address concluded the storm-shortened convention that sought to galvanize the conservative Republican base behind Romney and frame the upcoming election as a referendum on Obama's presidency.

When Romney finished, clouds of red, white and blue balloons floated down as his running mate, Rep. Paul Ryan, joined him on stage, followed quickly by their wives and families amid the cheers and confetti.

Protesters briefly interrupted Romney early in the speech, with one shouting "people over profits" in reference to the multimillionaire former businessman's career in private equity. The crowd shouted "U.S.A, U.S.A" to drown them out, and one was removed after a brief scuffle.

Ryan energized the convention on Wednesday night with a powerful attack on Obama that championed conservative principles. On Thursday, speakers including Hollywood legend Clint Eastwood laid the foundation for Romney's highly anticipated speech that was intended to provide Americans just tuning in to the election campaign with an introduction to the man and candidate.

Appealing to the base, showing a personal side

CNN analysts called the speech successful in appealing to the base and showing some of Romney's personal side, but also said it was business-like at times and offered no new ideas or proposals from the candidate who has been on the trail for the past year.

"It had a lot of heart. It needed more soul. It needed more poetry," said CNN senior political analyst David Gergen, adding that Romney described a "Norman Rockwell America" that is far from the state of the nation today.

Gloria Borger, the CNN chief political analyst, said the themes Romney emphasized showed what audience his campaign wanted to reach -- Obama supporters disappointed with the president today, and women who polls show favor Obama today.

The speech provided a biographical look at Romney's life, talking about his parents -- who both held or ran for political office -- and his Mormon faith and how they shaped his life. Earlier, members of his church gave testimonials to Romney's help and compassion during past crises, such as the early death of one couple's son.

In an effort to show a personal side after criticism for being stiff and impersonal at times on the campaign trail, he told stories of family life such as the single rose his father, former Michigan Gov. George Romney, gave his mother every day, and the incessant household noise in raising five boys. Paying tribute to his wife, Ann, Romney expressed admiration for the role of women in society in a bid to appeal to women voters who polls show currently favor Obama.

Romney also injected humor, telling how he decided against approaching his church to invest in his new company as a young man.

"I figured it was bad enough I might lose my investor's money, but I didn't want to go to hell, too," he said.

Romney then focused on his ideas for ending the nation's economic challenges -- lingering high unemployment, sluggish economic recovery, a chronic deficit and debt problem.

"Today the time has come for us to put the disappointments of the last four years behind us, to put aside the divisiveness and the recriminations, to forget about what might have been and to look ahead to what can be," Romney said. "Now is the time to restore the promise of America. Many Americans have given up on this president but they haven't ever thought about giving up. Not on themselves. Not on each other. And not on America."

'Jobs, lots of jobs'

Focusing his message on the economy -- an issue that polls show him winning with voters -- Romney said the country's needs are not "complicated or profound."

"What America needs is jobs, lots of jobs," he said, arguing Obama offers more of the same to people who "now believe that the future will not be better than the past."

He repeated campaign-tested promises to repeal Obama's 2010 health care reforms detested by conservatives, increase domestic oil production, reduce government regulations and cut taxes on businesses. Romney also pledged to assert U.S. might and influence around world, saying "we will honor America's democratic ideals because a free world is a more peaceful world."

Other issues mentioned reflected traditional conservative policies -- opposition to gay marriage and abortion, no tax increase for the middle class, and strong support for Israel.