John Edwards wears jeans on the stump. Mike Huckabee plays bass guitar with local bands before his speeches and all the main candidates have been accompanied by family or people close to them on the campaign trail.
Their aim is to win perhaps the oldest game in a U.S. presidential race -- to persuade voters to like them.
Candidates trumpet their voting records, their experience and their strong principles. But unless they pass a basic test of likeability, their chances of making it all the way to the White House are slim.
"Image is extremely important. Issues always come in a dismal last," said Saint Louis University political science professor Ken Warren.
"Most Americans don't follow politics very closely. Most people don't really know where these candidates stand on these various issues except in a very general sense."
Before the primary elections that will determine who will represent the Democratic and Republican parties in the November 2008 contest for the presidency, all the candidates have tailored their personal narratives to woo specific constituencies.
To try to project the authenticity voters respond to, they must also appear comfortable in the many contrived situations they encounter on the campaign trail.
In a scene repeated throughout the campaign, Republican Huckabee dropped into a restaurant in Columbia, South Carolina, on Saturday and conducted seemingly casual conversations with diners eating breakfast in the midst of a scrum of reporters.
Likability versus toughness?
In one measure of likeability, a higher percentage of Democratic voters associated the terms "friendly" and "down to earth" with Sen. Barack Obama than with Sen. Hillary Clinton or John Edwards, according to a Pew Research survey in September.
On the Republican side, former New York Mayor Rudy Giuliani scored higher for those traits than rivals Sen. John McCain, former Massachusetts Gov. Mitt Romney and Fred Thompson, the actor and former senator, the survey found.
Other polls have shown that Clinton is more likely to polarize voters than other candidates and that people who dislike her are prone to hold that opinion strongly.
In one example, Lynn Kartchner, a gun shop owner in the ranching town of Douglas on the Arizona-Mexico border, said in an interview: "She's a horrible person just like her husband (former president Bill Clinton)."
But Michael Dimock of the Pew center feels a candidate's ability to seem friendly is not necessarily a decisive factor in swaying voters.
McCain, for example, is perceived by many Republican voters as a strong leader. As a result he may not be harmed by a parallel perception that he is less friendly than other candidates, Dimock said.
The same poll that rated Clinton as less friendly than her rivals also rated her "tough" and "smart" to a majority of Democratic voters. Giuliani was also rated as "energetic" and "tough" to a large percentage of Republicans.
The key is to reinforce the positive characteristics that people already associate with a candidate," said Dimock. "But people don't always apply the same benchmarks."
Candidates often cherry pick parts of their personal stories -- a tough upbringing or a strong family -- to project favorable images of themselves to particular voter groups.
The possibility that Clinton could become the first woman president of the United States has a particular resonance for many women and older voters.
Kay Baccam, 38, who works at an Iowa spice plant, said she liked Thompson but was leaning toward Clinton in part because of her gender.
"She would be the first woman (president) in history. That's a good role model for kids and women," she said.
Obama has presented his life story as an asset, while other candidates have used battles with ill health either personally or in their families as reasons for voters to like them.
Huckabee's rise in recent polls is based in part on perceptions of his conservative credentials but also on the sense that he is an easy-going, humorous man who successfully battled a weight problem -- a struggle many voters relate to.
Asked at the South Carolina restaurant which was easier, to run for president or to lose weight, he said: "They are both pretty tough. (But) losing weight is the only time that a politician actually tries to jettison something."