The new scarlet letter in politics is "R"—as in "Rich."
From Hillary Clinton to congressional, gubernatorial and state-legislature candidates around the country, wealthy candidates are getting pummeled on the campaign trail because of their large fortunes. Once seen as symbols of the American dream, today's wealthy candidates are trying desperately (and often awkwardly) to deny their wealth and appear as middle class, everyday Americans.
The most heated class battle is taking place in the Illinois governor's race. Billionaire private equity chief Bruce Rauner is getting pilloried for his nine homes and $53 million in income in 2012. As he admitted to the Chicago Sun-Times, "I'm probably .01 percent."
News that Rauner belongs to an exclusive wine club, called The Napa Valley Reserve, that typically costs more than $100,000 to join has been a boon to his populist opponent, Democratic Gov. Pat Quinn.
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"You just can't get more out of touch than Republican billionaire Bruce Rauner," Izabela Miltko, a spokeswoman for Quinn, said in a statement Tuesday. "While enjoying a luxury $140,000 wine club membership, Republican Bruce Rauner actually proposed to cut the minimum wage."
A headline Tuesday from The Washington Post read, "Bruce Rauner spends more on wine than average Illinois households spend on everything." Meanwhile, Quinn has been on a weeklong "minimum wage challenge," struggling to live on minimum wage and meals of bananas and graham crackers.
In Georgia, Senate Republican candidate David Perdue, former CEO of Dollar General, is lagging in the polls behind Michelle Nunn in a race that has cast a spotlight squarely on Perdue's wealth. A new attack ad shows former millworkers from North Carolina who lost their jobs when their company, Pillowtex, shut down shortly after Perdue became its CEO in 2002.
"He walked away with his $1.7 million and he didn't care if we had a dollar in our pockets," said one worker in the ad.
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The class war on the campaign trail picks up where the Romney-Obama battle in 2012 left off. Obama's success at portraying Romney as an out-of-touch millionaire was highly effective at a time when many Americans are still struggling with high unemployment, low wages and a widening wealth gap.
Yet this time around, it's also Democrats getting attacked, suggesting that the bonfire of populist politics unleashed by the Dems in 2012 may now consume some of their own. Bruce Braley in Iowa, Sean Eldridge in New York and even Hillary Clinton are all being criticized for being too rich to care.
And some of their worst moments are the result of trying to appear nonwealthy. When Clinton said she and her family were "dead broke" when they left the White House, Clinton was pilloried in the press. News of the Clintons lavish speaking fees, private jets and questions about their foundation have all challenged Clinton's image as the champion of blue-collar America that dominated her run in 2008.
Even before the current election cycle, millionaire candidates weren't faring well. According to the Center for Responsive Politics, 263 millionaire candidates who put at least $500,000 of their own money into their campaigns have run for congressional office since 2002. But 84 percent of them lost.
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In 2012, of the 48 millionaire self-funded candidates who ran for congressional office, only 12 won.
As the Center for Responsive Politics said, "Though they don't lack for money, self-funded candidates typically lose at the polls."
—By CNBC's Robert Frank