MERRIMACK, N.H. — Perhaps the most eye-popping statistic to come out of last week’s Iowa caucuses was Bernie Sanders’s overwhelming advantage among young voters. According to the Iowa entrance poll, Sanders beat Hillary Clinton 84 percent to 14 percent among Democrats aged 17 to 29. He also won voters aged 30 to 44 by a 21 percentage point margin. But Clinton easily won among voters aged 45 and older, allowing her to essentially tie with him in the state. Pre-election polls in New Hampshire suggest that the age divisions in the Democratic electorate could be at least as dramatic here.

AGE SANDERS CLINTON 17-29 84 14 30-44 58 37 45-64 35 58 65+ 26 69 Sanders won Iowa’s youth vote overwhelmingly Edison Research Iowa Entrance Poll

These differences are really something. In 2008, Barack Obama performed better than Clinton among younger Democrats, but not by nearly the margin that Sanders won them in Iowa. And although generational affinity might have explained some of Obama’s success with young voters — Obama was 46 years old at the time of the 2008 primaries — it doesn’t work for the 74-year-old Sanders, who is six years older than Clinton.

When you see a demographic trend this striking, it usually has multiple explanations. In this article, I’ll focus on how younger Americans view political labels like “socialist” and “libertarian” differently than older ones, and how that might be helping Sanders. I’ll explore several alternative explanations for Sanders’s support among young Americans in a follow-up article next week.

Young voters have a more favorable view of socialism

Bernie Sanders proudly describes himself as a “socialist” (or more commonly, as a “democratic socialist”). To Americans of a certain age, this is a potential liability. I’m just old enough (38) to have grown up during the Cold War, a time when “socialist” did not just mean “far left” but also implied something vaguely un-American. If you’re older than me, you may have even more acutely negative associations with “socialism” and may see it as a step on the road to communism. If you’re a few years younger than me, however, you may instead associate “socialism” with the social democracies of Northern Europe, which have high taxes and large welfare states. Sweden may not be your cup of tea, but it isn’t scary in the way the USSR was to people a generation ago.

Indeed, views of socialism are highly correlated with a voter’s age. According to a May 2015 YouGov poll, conducted just before Sanders launched his campaign, a plurality of voters aged 18 to 29 had a favorable view of socialism. But among voters 65 and older, just 15 percent viewed socialism favorably, to 70 percent unfavorably.

Young voters don’t necessarily back socialist economics

That doesn’t mean America is undergoing a leftist or revolutionary awakening, however. The biennial General Social Survey has a long-standing question about wealth redistribution, asking Americans whether the “government in Washington ought to reduce the income differences between the rich and the poor … perhaps by raising the taxes of wealthy families or by giving income assistance to the poor.” While no one question can summarize Sanders’s left-of-center economic program in a sentence, this is probably about as close as you’re going to get; his plan would raise marginal tax rates to as high as 77 percent on the very richest Americans to pay for a host of social programs.

The General Social Survey question asks respondents to place themselves on a 7-point scale ranging from favoring government efforts at redistribution to opposing them. To make things a little more intuitive, I’ve translated those responses to a 100-point scale, where 0 represents the most conservative/right-wing position (no redistribution!), and 100 the most liberal/left-wing position (hell yes, redistribution!). The chart below summarizes how both Americans overall and Americans aged 18-29 have responded to the question over time.

Americans end up pretty much in the middle of the road. Whereas 50 would represent an exactly centrist position, the average score among all Americans in 2014 (the most recent edition of the survey) was 54. Americans aged 18-29 scored a 60, just slightly further to the left. But these are really modest differences, and they haven’t changed much over time. In 1996, 20 years ago, the average response among all Americans was a 54, and the average among Americans aged 18-29 was a 59, almost exactly the same as now. It’s possible that Sanders will trigger a shift toward more support for economic redistribution in the future, but there hasn’t been one yet.

What socialists and libertarians have in common

Just as “socialism” is becoming more popular with young Americans, so is another label that implies a highly different set of economic policies. Americans aged 18-29 are much more likely than older generations to have a favorable view of the term “libertarian,” referring to a philosophy that favors free markets and small government. Indeed, the demographics of Sanders’s support now and Ron Paul’s support four years ago are not all that different: Both candidates got much more support from younger voters than from older ones, from men than from women, from white voters than from nonwhite ones, and from secular voters than from religious ones. Like Sanders, Paul drew more support from poorer voters than from wealthier ones in 2012, although that’s not true of libertarianism more generally.

If both “socialism” and “libertarianism” are popular among young voters, could it be that younger voters have a wider spread of opinions on economic redistribution, with more responses on both the “0” and “100” ends of the scale? It could be, but that’s not what the data shows. In fact, on the General Social Survey question I mentioned earlier, younger Americans were more likely than older ones to be concentrated toward the center and not toward the extremes on the redistribution issue.

The cynical interpretation of this is that the appeal of both “socialism” and “libertarianism” to younger Americans is more a matter of the labels than the policy substance. Relatedly, it’s hard to find all that much of a disagreement over core issues between Clinton and Sanders, who voted together 93 percent of the time when they were both in the Senate from 2007 to 2009.

But terms such as “liberal” and “conservative” are fairly cynical also, at least in the way they’re applied in contemporary American politics. Rather than reflecting their original, philosophical meanings, they instead tend to be used as euphemisms for the policy positions of the Democratic and Republican parties, respectively. Those parties’ platforms are not all that philosophically coherent, nor do they reflect the relatively diverse and multidimensional political views of individual Americans. Instead, the major American political parties are best understood as coalitions of interest groups that work together to further one another’s agendas.

What’s distinctive about both the Sanders and Ron Paul coalitions is that they consist mostly of people who do not feel fully at home in the two-party system but are not part of historically underprivileged groups. On the whole, young voters lack political influence. But a young black voter might feel more comfortable within the Democratic coalition, which black political leaders have embraced, while a young evangelical voter might see herself as part of a wave of religious conservatives who long ago found a place within the GOP.

A young, secular white voter might not have a natural partisan identity, however, while surrounded by relatively successful peers. In part, then, the “revolutions” that both Sanders and Paul speak of are revolutions of rising expectations. We’ll explore this theme more fully in Part II of the series, and consider some alternative explanations for Sanders’s success.

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