Sen. Ted Cruz (R-TX) announces his presidential candidacy March 23, 2015 at Liberty University in Lynchburg, Virginia. (Mark Wilson/Getty Images)

David Greenberg is a professor of history at Rutgers University and the author of a forthcoming history of political spin.

Candidates of the left, right and center have something in common: They all want to be seen as populists. Hillary Clinton attacks income inequality and issues booklets showing how well she stacks up, even against Sen. Elizabeth Warren, as a booster for the embattled middle class; Sen. Marco Rubio invokes the American dream; Mike Huckabee and putative libertarian Sen. Rand Paul are against giving President Obama a free hand to negotiate the Pacific trade pact.

Meanwhile, pundits and journalists prowl for populists everywhere: Sen. Ted Cruz is a “populist egghead.” Rubio showcases “populist themes” of up-by-the-bootstraps success. Huckabee is going “full populist.” And Paul’s “populist country music video” blamed banks and Washington for lost jobs. The only top-tier contender seemingly unlinked to populism is Jeb Bush — son of one president, brother of another, backed by establishment heavies — although even his approach has been labeled “populist,” too.

Yet these aren’t modern versions of William Jennings Bryan, fiery crusaders jousting on the campaign trail, railing against politicians who “only legislate to make the well-to-do prosperous” and thereby “crucify mankind upon a cross of gold.” All the candidates have taken what was once a very specific ideology and extracted their favorite parts, selectively interpreting the vision and generally bowdlerizing it. With so many different policies and philosophies vying for the label, the word “populist” is in danger of losing all meaning. If we’re all populists, it’s because populism has been stretched so thin.

Populism entered the political lexicon to describe the platform of the radical farmers’ movement of the 1880s and 1890s. The original capital-P Populists — farmers and miners squeezed by the unfettered capitalism of the Gilded Age — championed egalitarian economic policies: looser credit, nationalized railroads, breaking up the era’s dominant trusts. For a brief spell, they forged a robust party called the People’s Party, which elected candidates to dozens of statewide offices across the South and West and fused with the Democrats in 1896 to nominate Bryan for president.

As important as their economic agenda, the Populists pressed their case using a signature language and symbolism. Rooted in the ideas of Thomas Jefferson and Andrew Jackson, they invoked the virtue of the common man and the malevolence of powerful elites. Moral in their tone, given to demonizing their enemies and purporting to speak on behalf of the otherwise voiceless “people,” the Populists bequeathed to later generations not only an economic philosophy but also a style and sensibility — which a variety of grass-roots movements have over the decades adopted and adapted to their own ends. You hear it today in the way Cruz rails against “political elites in Washington and New York,” or in Sen. Bernie Sanders’s impassioned descriptions of “a rigged economy, which works for the rich and the powerful.”

This style and language have been enduring and versatile, as historian Michael Kazin shows in “The Populist Persuasion: An American History,” his go-to guide to the movements that have worn the mantle. Prohibitionists, labor unions, anti-Communists and civil rights activists have been among the many groups to appropriate populist tropes and attitudes. Ironically, however, after World War II — and especially after the 1960s — it was conservatives such as Richard Nixon, George Wallace and Ronald Reagan who most successfully reinvented populism, mobilizing the hard-pressed working class against such despised liberal elites as government bureaucrats, Washington experts, university professors and the news media.

In the 1970s and 1980s, Democrats, traditionally the party of the working class, strove to reclaim the populist ground. Despite offering a more egalitarian economic program than the Republicans, they found themselves perennially cast as out of touch on social and cultural issues, including drugs, crime and welfare. Even on economics, GOP candidates often managed to shed their image as friends of big business to sell their low-tax, anti-regulatory politics as a boon to struggling entrepreneurs.

Eventually, however, the pendulum swung the other way. In 1992, Bill Clinton won back Reagan Democrats with a proudly populist campaign that boasted of “putting people first.” Clinton’s liberalism was really a fusion of technocratic and populistic elements, but economic fairness was its central theme, and it helped make the Democratic Party viable again in national elections. As president, he followed through, notably with the landmark 1993 budget bill, which made the tax code more progressive, extended relief to lower-income Americans and began paying down the deficit for the first time in decades, while also pressing for welfare reform in the form of “workfare.”

Seeking the White House in 2008, Hillary Clinton continued this tradition, positioning herself to Barack Obama’s left as she called for, among other things, an end to the George W. Bush-era tax cuts and limits on executive pay.

The problem for her is that populism has always been a style as much as a set of policies. And since the 1960s in particular, the slogans and visuals of the campaign trail have placed ever greater weight — sometimes absurdly so — on fashioning every candidate as an unpretentious outsider, from Jimmy Carter’s blue jeans to Sarah Palin’s hockey shtick. As Clinton has ascended over the past two decades to the positions of senator and secretary of state, it has inevitably grown harder for her to present herself as an insurgent raging against the Washington insiders.

And while we might lament what seems like the occasional triumph of image over substance, the truth is that symbolism matters in politics, and properly so. When Thomas Jefferson abjured the regal dress that George Washington and John Adams wore, or when Andrew Jackson threw open the White House doors at his inauguration to welcome the muddy-booted rabble who had trekked to the capital from the Tennessee frontier, they were making statements about their views of democracy and the role of the president. Sometimes, it’s true, politicians devise phony-baloney stunts to remake their aristocratic personas — Connecticut-bred George H.W. Bush famously munched pork rinds to prove his Texas bona fides. But political leadership understandably requires an ability to show affinities with ordinary people, however far from the original notion of populism that quality may be. The presidential candidate who can’t do that is likely to have a hard time if elected.

So we now have populisms of policy and of personal image — on the left and the right. For the past quarter-century, the very mention of the word has evoked a morass of muddy imprecision. In 1993, Michael Kinsley concluded that “populist” frequently means “nothing more than ‘popular.’ ” Two years later, Kazin despaired that the label was applied to “everything from Bruce Springsteen to Rush Limbaugh to loose-fitting cotton trousers.” Today pundits reach for the term when they really mean something very different — that a candidate is down to Earth or has an easy rapport; that he comes from hardscrabble roots or affects an unpretentious demeanor; that she speaks with moral fervor or gets angry when denouncing the opposition. All it really means is “I’m on your side” — a declaration that, obviously, no candidate would disavow.

So why not retire the term? Its promiscuous application has usually meant forgetting and forsaking key parts of the original Populists’ agenda. This year’s Republican candidates — an assortment of senators, governors, a surgeon, a CEO — may rail against Washington and claim to fight for the little guy, but in most cases, their view of government’s role in economic life couldn’t be more starkly opposed to the Populists’ ideals. On the other hand, while Clinton can fairly claim to have voiced the concerns of those lower on the economic ladder, her years in establishment circles have made it hard for her to denounce a rigged system with the fire-and-brimstone zeal that the populist label suggests. Even Warren was until the 1990s a Reagan Republican — long past the time when it became clear whose interests the GOP’s economic agenda primarily served.

Most important, all of these candidates espouse some views that would run afoul of Populist doctrine, or exhibit political attributes that would raise the suspicions of the beleaguered farmers and miners of the late 1800s.

But if the overuse of “populism” can induce exasperation, it’s also possible to survey the landscape and be cheered. Yes, we’ll still be treated to wince-inducing presidential announcements, like Huckabee’s recent proclamation that “it was here in Hope that . . . I learned how to handle a firearm and a fishing pole,” as if his rural upbringing provided all we needed to know about what kind of president he’d be. But even if it’s just for appearance’s sake, it’s probably a positive development that across the spectrum, presidential contenders are scrambling to claim the populist inheritance. That alone suggests which way the winds of public opinion are blowing — and in which direction the successful candidates will have to cast their sails.

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