In America, the term “middle class” has long been used to describe the majority of wage and salary earners, from those receiving a median annual income of around $50,000 to those who earn three or four times that amount. Whether Democrat or Republican, politicians from across the political aisle claim to represent the middle class—that vast-yet-amorphous segment of the population where the managers and the managed all seem to fit together.

The term has always been somewhat problematic when it comes to politics. As Joan C. Williams observes in her 2017 book, “White Working Class: Overcoming Class Cluelessness in America,” a “central way we make class disappear is to describe virtually everyone as ‘middle class.’ ” The majority of Americans see themselves as middle class, including those in the top 10% earning several times the average income. According to Williams, a close friend of hers who “undoubtedly belonged to the top 1%” once referred to herself as middle class, a perspective that the author describes as “class cluelessness.”

This cluelessness was also evident in a New York Times article last summer titled “What Middle Class Families Want Politicians to Know,” which included interviews with a number of purportedly middle class families with household incomes of up to $400,000 (only one of the interviewees earned less than $100,000, with the average around $200,000).

The fact that people who earn a quarter-million dollars annually place themselves in the same category as those earning $70,000 tells us just how politically useless the term “middle class” has become in contemporary America. Even when we take into account geographic factors and fluctuations in the cost of living, there is little rational justification for categorizing a $60,000-a-year blue-collar worker with a lawyer or doctor earning in excess of $200,000.

Of course, some may argue that one’s class is based largely on her own experience and perspective, but this confuses psychological feelings with concrete social and economic realities. As C. Wright Mills pointed out in his classic study, “White Collar: The American Middle Classes,” just because people “are not ‘class conscious’ at all times and in all places does not mean ‘there are no classes’ or that ‘in America everybody is middle class.’ ” Although subjective feelings are no doubt important, to accept that everyone who identifies as middle class must be middle class is to disregard objective economic realities.

One’s class consciousness (or lack thereof) has important implications for one’s political attitudes, and in America class consciousness has always been somewhat lacking compared to other countries. The United States has never had a true aristocratic class or feudal property relations like those in Europe, and in the 19th century, the “middle class” essentially stood for small capitalists and propertied farmers. Between the mid-19th century and mid-20th century, the country was transformed, in Mills’ analysis, from a “nation of small capitalists into a nation of hired employees”—a trend that sociologists call “proletarianization.”

In the post-World War II era, thanks to the struggle of labor and the policies of the New Deal, which aimed to reduce inequality and mediate class tensions, many in the working class became comfortably middle class. In other words, the proletariat turned into a kind of “petty bourgeois,” adopting the same values and attitudes as their employers, while accepting the status quo after a few adjustments. Ironically, this ended up undercutting more radical labor movements while preserving the economic system, which eventually came back to bite working people and their children.

The new middle class flourished until the capitalist class decided to revolt against the legacy of the New Deal toward the end of the 20th century. In the contemporary era, many who would have been middle-class in the postwar years have effectively been proletarianized once again, and economic inequality has returned pre-Great Depression heights. Proletarianization, Mills explained, “refers to shifts of middle-class occupations toward wage-workers in terms of: income, property, skill, prestige or power, irrespective of whether or not the people involved are aware of these changes. Or, the meaning may be in terms of changes in consciousness, outlook, or organized activity.”

The proletarianization of the middle class over the past 50 years has had an enormously detrimental effect on communities across the country, but it has taken quite a while for many working people in America to recognize their new situation in terms of consciousness and outlook. The enduring popularity of the term “middle class” reflects this state of affairs.

In the Democratic primaries, only one candidate has deliberately chosen to use “working class” over “middle class.” Not surprisingly, that candidate is Sen. Bernie Sanders. “I am a candidate of the working class,” Sanders recently declared on Facebook. “I come from the working class. That is my background, that’s who I am. I fought for the working class as a mayor, a Congressman and a Senator. And that is the kind of president that I will be.” Sanders, whose campaign is 100% grassroots-funded, wrote in a column last week for the Des Moines Register, “… our campaign is focused on making sure the government stops representing billionaires and start representing us — the working class of this country.”

Though it may seem like a somewhat trivial distinction, when we look at the rest of the Democratic field, it’s clear that Sanders has indeed distinguished himself from the other top candidates. For example, Sanders’ opponent Joe Biden frequently speaks of the middle class but rarely the working class. “This country wasn’t built by Wall Street bankers and CEOs and hedge fund managers. It was built by the American middle class,” Biden declares on his campaign website, where he says that the middle class “isn’t a number,” but a “set of values.” (In a way this is correct, but not in the sense that Biden seems to think.)

On the more progressive Sen. Elizabeth Warren’s website, where she lists her numerous plans, one searches in vain for any references to the working class, though there are plenty to the middle class.

How much this actually matters is, of course, debatable, but the term “working class” undoubtedly has far more implications and political significance than “middle class,” which, like many overused words in the political lexicon, has lost all meaning. By using “working class” instead, Sanders appears to be trying to increase class consciousness in America, where those in the ruling class have often demonstrated the highest level of class consciousness (never failing to use their abundant resources to protect and advance their own interests).

The more young and working-class people come to recognize their own situation and place in the 21st century American economy, the more they seem to embrace “socialist” policies that are rejected by “middle class” sensibilities.

In the Democratic primaries, only one candidate has made raising levels of class consciousness part of his campaign strategy, and in an election that could very well be determined by working-class voters, this may be the strategy to defeat Trump.