The 2012 presidential campaign, marked by scorched-earth rhetoric and sharply opposing policies, could turn tonight on something as simple as whether Republican Mitt Romney can comfortably tell a few jokes about himself, analysts said.
Romney, dogged by what polls show is an inability to connect with voters, will formally accept his party's nomination in a speech watched live by millions on television.
But many said Romney's ability to overcome his stiff image and endear himself to voters at the crowning moment of the Republican National Convention likely will go a long way toward deciding the fate of his six-year slog toward the White House.
"It's really sink or swim for him," said David Paleologos, director of the Suffolk University Polling Research Center in Boston, who has tracked Romney's career since his days as Massachusetts governor.
"He has this one opportunity to define who he really is. He's suffered from this likability gap. But this is his prime-time chance to change it," Paleologos said.
Darryl Paulsen, a retired University of South Florida political scientist and a Republican, said Romney should look to Ronald Reagan's 1980 nomination-acceptance speech as a model of image-changing that led to the White House.
Reagan was able to outline a vision of a new, more modest government in his address. But even more powerfully, he altered the perception Democrats had helped create of him as a right-wing reactionary, Paulsen said.
It resulted in victory over incumbent Democrat Jimmy Carter.
Romney should draw heavily from Reagan's skill at self-deprecating humor, Paulsen said.
"Time is running out for Romney," Paulsen said. "But people want to see a candidate who is comfortable in his own skin. I'm not expecting a policy speech. You'll hear a personal-relationship kind of speech that also says we can move this nation ahead."
Romney's wife, Ann, apparently has done her part.
Many analysts said her Tuesday night address to the convention, replete with memories of family and a love affair spanning more than four decades, humanized her husband for voters far more than his years of campaigning had.
But Ann Romney also may be a tough act for the candidate to follow, some said.
"His warmth, his kindness, that's something she was able to express better than anyone," said Kathy King, chairwoman of the Manatee County Republican and part of the Florida delegation. "Mitt is getting more agile on his feet. But he's got to deliver."
Jay Goldfarb, a Palm Beach County delegate, said he was optimistic.
"He's going to knock it out of the park, I just feel it," Goldfarb said.
Romney the jobs creator, successful businessman and potential fixer of the nation's stalled economy is a role certain to be emphasized in Romney's speech.
After all, Romney's skills as a CEO have been central to his campaign pitch.
But since his selection of running mate Paul Ryan and the GOP's adoption of a tough national platform, such divisive positions as a call for tougher abortion laws, strict enforcement of immigration standards and the revamping of Medicare and Medicaid have moved to the forefront.
Those topics will likely get short shrift in tonight's address. Instead, Sen. Marco Rubio's introduction of Romney will burnish the candidate's leadership skills and his free-market advocacy. Several Olympic athletes also will take the stage to tout Romney's guidance of the 2002 Winter Games.
Still, some Republicans said they worry about Romney's candidacy becoming blurred.
"Jobs, jobs, jobs," Goldfarb said. "That's all he's got to talk about. This election is going to be about the economy. He shouldn't get distracted."