Defining Moment: Romney Speaks to Convention Tonight

It will be Romney's biggest television audience to date as much of the nation tunes in, giving some voters their first extended look at the 65-year-old former Massachusetts governor, who unsuccessfully sought the Republican nomination in 2008.

Romney, who can often come across as stiff, faces the challenge of making Americans feel more comfortable with him.

He has a hard act to follow after the ringing "you can trust Mitt" endorsement delivered by his wife, Ann, on Tuesday night, a speech that was widely viewed as one of the most significant ever given by an aspiring first lady.

Romney got a strong testimonial on Wednesday night from his vice presidential running mate, Wisconsin congressman Paul Ryan, who generated the most enthusiasm so far at the convention with his address.

"After four years of getting the run-around, America needs a turnaround, and the man for the job is Governor Mitt Romney," Ryan said.

As portrayed by Democrats, Romney is alternately a heartless corporate raider, wealthy elitist, tax evader and policy flip-flopper who should not be trusted with the keys to the White House.

Despite the attacks, Romney is running even with Obama in opinion polls in a race that is too close to call. A Reuters/Ipsos poll on Wednesday showed the two men tied at 43 percent each.

But Obama has the advantage over Romney in likability, an important characteristic that may mask other problems that the Democratic incumbent has in persuading voters to give him four more years.

There was no shortage of advice from Republican heavyweights as Romney launches his final stretch of campaigning before the Nov. 6 election.

Arizona Senator John McCain, the Republican presidential nominee in 2008 who lost to Obama, said Romney needs to accomplish two tasks: one, convince Americans "that they believe in him and trust in him, and two, that he has a concrete plan to get our economy back on the right track."

"We've got to reduce the unfavorables, and many Americans will be looking at him for the first time," McCain told Reuters.

Former Florida Governor Jeb Bush -- son of former President George H.W. Bush, another politician known during his tenure for a sometimes aloof demeanor -- said Romney had to do more to reach voters on a personal level.

"What he has to do a little better, I think -- and I think he's more than prepared to do this -- is to connect with other people's aspirations and their hopes," he told CBS's "This Morning" program.

LONG JOURNEY

Romney's big speech culminates a long journey. After failing to win the Republican nomination in 2008, he plotted a return to the political arena. This year he was tested time and again by a series of conservative alternatives from Newt Gingrich to Rick Santorum. He outlasted all of them.

Romney has some inherent advantages in his race against Obama. He is topping the Democrat in campaign donations, and the weakness of the U.S. economy, with a staggering 8.3 percent unemployment rate, gives him a lethal argument for change.

Even so, Romney is far from closing the deal. It is unclear whether his economic proposals for tax cuts and deregulation of industries would rekindle growth and keep taxpayer dollars flowing into the Treasury to pay for expensive government entitlement programs, such as the Medicare health insurance program for seniors, which he wants to reform.

Taking a final shot at Romney before he takes center stage, Obama insisted the race should hinge not on personality but on stark policy choices.

"This isn't a matter of who is more patriotic or who is more empathetic towards people or who is nicer. It's a hard-headed assessment of what makes our economy grow," Obama told Time magazine in an interview published on its website on Thursday.

But Obama, offering a rare compliment to his opponent, said he admired that Romney "seems to walk the walk and not just be talking the talk" on his Mormon faith. Romney's Mormonism is a sensitive subject with some evangelical Christian voters who are an important part of the Republican base.

CHANCE TO COUNTER NEGATIVE ADS

Romney's convention speech offers him a chance to break through the blizzard of negative television ads about him.

Republican delegates at the Tampa convention recommended Romney be himself in his speech, talk about his background as a businessman and Olympics organizer, and offer a way forward.

New York State Senator Mike Nozzolio said Romney needs to explain to voters in an understandable way that he is "competent, directed, focused, and can make the message appeal to folks around the kitchen table.

"He's going to be the guest of millions of Americans in their living rooms, and this is a wonderful opportunity for people to understand what he knows and where he wants to take us," Nozzolio said.

Donna Gosney, of Boone County, West Virginia, wearing a plastic coal miner's helmet festooned with political stickers, said Romney simply needs to say what he would do to reignite substantial job growth.

"We've got 2,000 reasons in Boone County to vote for Mitt Romney. They're all miners without jobs," she said.

Frank Steed, of Navarro County, Texas, said Romney should not worry about trying to appear warm and fuzzy.

"He is who he is," Steed said. "And I think he ought to be proud of that. He's a businessman. He's not a politician."