(CNN) -- Sen. Barack Obama is saddled with a potentially toxic image problem: that he has an elitist attitude.
Sen. Barack Obama mingles at the Penn State dairy farm.
It has made him a target of attacks from Democratic rival Sen. Hillary Clinton and Sen. John McCain, the presumed Republican nominee.
It's ironic that one presidential candidate could hang that label on another, said Dr. Drew Westen, professor of psychology and psychiatry at Emory University in Atlanta, Georgia, and author of "The Political Brain."
"If you think you should be president, by definition you are an elitist, only because you believe that of the 300 million people in America, you are the best person to run it," he said. "There can't be a more elitist statement than that."
Obama's opponents made the elitist charge after the senator from Illinois said some small-town Pennsylvanians are understandably "bitter" over the government's failure to reverse their economic decline and, in their frustration, "cling to guns and religion." He made the statement at a recent fundraiser in San Francisco, California. Watch how Obama is fighting the elitist label »
Obama defended his remarks but said he could have worded them better.
Clinton said his comments were "elitist, out of touch and frankly, patronizing."
McCain agreed that the remarks were "elitist."
Branding a rival elitist is not new in politics. Republicans for years have successfully labeled Democratic presidential candidates as the liberal elite. Portraying their rivals as latte-sipping, sushi-eating insiders, Republicans have connected with some voters by arguing that they understand the values important to the everyday person.
"It's a little like when politicians charge politicians with being politicians. It has the same feel to it: that if it sticks, it's because a candidate hasn't handled it well," Westen said.
Republicans painted George W. Bush's Democratic opponents Al Gore in 2000 and John Kerry in 2004 as elitists who were detached from average Americans, and the strategy worked.
How damaging the blow is, Westen said, depends on the target's response.
"The mistake that Kerry and Gore both made was to let that brand stick to them," he said.
"The only question is whether Obama fights it back and offers a different brand for himself than the brand that is starting to be given to him."
By definition, all the candidates exhibit the aura of elitism, because it's difficult to get a presidential campaign started without some degree of personal wealth.
It's ironic, Westen said, that of the three standing, the only one who isn't demonstrably wealthy is Obama.
Since leaving the White House, the Clintons have earned more than $109 million from book sales, speaking engagements, the presidential pension and her Senate salary, among other sources.
McCain, whose father and grandfather were Navy admirals, married into wealth. His second wife, Cindy, has a stake in her father's multimillion-dollar beer distributor company. The Associated Press estimated her worth at more than $100 million.
Whatever their current financial status, the candidates all like to convey the impression that they are not much different than the people they are trying to persuade to vote for them.
Obama, 46, who graduated from Columbia University and received a law degree from Harvard, often mentions growing up in a single-parent home. He says he and his wife just paid off their school loans in the past five or six years.
"I wasn't born into a lot of money. I didn't have a trust fund. I wasn't born into fame and fortune. I was raised by a single mother with the help of my grandparents," he said. "My mother had to use food stamps at one point."
Clinton, who has been reaching out to blue-collar voters with stories of how she learned to shoot a gun in Pennsylvania and photo ops hoisting a shot and a beer, often talks about her middle-class upbringing.
Clinton, 60, went to Wellesley College before attending law school at Yale. After graduation, she advocated for women and children's rights and became a staff attorney for the Children's Defense Fund.
She later became a partner in a law firm and was twice listed as one of the 100 most influential lawyers in the country.
The senator from New York frequently touts her 35 years of public service, including eight as first lady.
McCain spent a week traveling around on a "get-to-know-me" tour. He talked about how he was a rambunctious child with a chip on his shoulder.
McCain, 71, went to the United States Naval Academy and frequently jokes about finishing at the bottom of his class.
After graduation, he spent 22 years as a naval pilot. He was shot down on a bombing mission and spent five years as a prisoner of war in North Vietnam. He retired from the Navy in 1981 and, living in Arizona, became a member of the House the next year. He was elected to the Senate in 1986 and is serving his fourth term.
Dr. James Twitchell, an author, University of Florida English professor and commentator on American culture, said the whole elitism back-and-forth is "self-serving nonsense," pointing specifically to the similarities in the Democratic contenders' stories.
"Both senators are members of one of the more elite clubs [the Senate], attended the elite schools [Harvard, Yale] and are out for one of the most elite jobs," he said.
As the candidates get closer to the White House, they get farther away from "normal life."
They fight to show they still share the average American's values, visiting bowling alleys, diners and schools along the way.
"I do think it speaks to one of the conflicts that Americans have about their leaders, which is we want them to be like us, and we want them to be above us at the same time," Westen said.
"The issue comes down to two things. One is, do you let your opponent brand you as elite, in which case you are in a lot of trouble in American politics? And the second is, do you convey clearly to people that you understand them and the world they live in and the problems they face?" he said.
"In the case of Barack Obama, my guess is, this isn't going to stick terribly well because he does such a good job of connecting with people that the elitist charge is going to be a harder one to make people feel." E-mail to a friend
CNN's Candy Crowley contributed to this report.