Bernie Sanders is, so far, steaming towards the Democratic nomination. He leads in the national polls, and with the rest of the field divided, he’s expected to keep doing well long into the primary calendar.

However, his campaign has recently been hit hard by criticisms of some supporters’ intense and sometimes abusive behaviour, both online and off. And there’s a catch-all term used for a certain kind of male Sanders fan, ardent, vocal and sometimes belligerent: the “Bernie bro”.

Who is this person, and what do we know about him?

Where did the term come from?

It seems to have been coined (in the mainstream media at least) by the Atlantic’s Robinson Meyer in 2015, albeit styled as a single word, Berniebro. Writing at the start of Sanders’s campaign against Hillary Clinton, Meyer simply laid out a list of behaviours that readers might recognise from their Facebook feeds:

“The Berniebro is posting a video on his Facebook wall: You really have to watch this. Bernie Sanders says things that no other candidate would ever consider. These are real policy proposals that just might change the country.

Democratic candidates compete on the campaign trail: In pictures Show all 18 1 /18 Democratic candidates compete on the campaign trail: In pictures Democratic candidates compete on the campaign trail: In pictures Jessica Canicosa, a precinct captain for Bernie Sanders, waits to greet caucus voters at Liberty High School in Henderson, Nevada REUTERS Democratic candidates compete on the campaign trail: In pictures Hotel workers at the Bellagio in Las Vegas get to grips with voting papers during the Nevada caucuses AFP via Getty Images Democratic candidates compete on the campaign trail: In pictures A caricature of Bernie Sanders is projected on to a tree during a rally in Las Vegas EPA Democratic candidates compete on the campaign trail: In pictures A woman waits to have a photo taken with Elizabeth Warren during a town hall meeting in Las Vegas REUTERS Democratic candidates compete on the campaign trail: In pictures The threat of coronavirus and other germ-borne illnesses was on some voters' minds at the Democratic caucuses in Henderson, Nevada Getty Images Democratic candidates compete on the campaign trail: In pictures Former vice-president Joe Biden takes a selfie with a voter in Las Vegas ahead of the Nevada caucuses REUTERS Democratic candidates compete on the campaign trail: In pictures Amy Klobuchar changes her shoes backstage after giving a speech in Exeter, New Hampshire AFP/Getty Democratic candidates compete on the campaign trail: In pictures A warmly-wrapped-up dog attends an Elizabeth Warren event at Amherst Elementary School in Nashua, New Hampshire AFP/Getty Democratic candidates compete on the campaign trail: In pictures Bernie Sanders, who romped to victory in New Hampshire against Hillary Clinton in 2016, talks to the media in Manchester Getty Democratic candidates compete on the campaign trail: In pictures Joe Biden was hoping to improve on his poor showing in Iowa in the New Hampshire primary Reuters Democratic candidates compete on the campaign trail: In pictures Elizabeth Warren, renowned for giving time to supporters for selfies, works the crowd at the University of New Hampshire in Durham Getty Democratic candidates compete on the campaign trail: In pictures Joe Biden takes a selfie with a supporter and his child outside a campaign event in Somersworth, New Hampshire on 5 February Reuters Democratic candidates compete on the campaign trail: In pictures Elizabeth Warren and Bernie Sanders quarrel after a confrontation in a TV debate in which Sanders claimed that Warren was not telling the truth about a conversation in which she claimed he had said a woman could not win the presidency on 14 January AP Democratic candidates compete on the campaign trail: In pictures Supporter Pat Provencher listens to Pete Buttigieg in Laconia, New Hampshire on 4 February Getty Democratic candidates compete on the campaign trail: In pictures Pete Buttigieg speaks at a campaign event in Concord, New Hampshire while awaiting the results of the Iowa caucus Reuters Democratic candidates compete on the campaign trail: In pictures Elizabeth Warren is presented with a balloon effigy of herself at a campaign event in Nashua, New Hampshire on 5 February Reuters Democratic candidates compete on the campaign trail: In pictures A Trump supporter rides past a rally for Amy Klobuchar in Des Moines, Iowa on 14 January AP Democratic candidates compete on the campaign trail: In pictures A man holds up a sign criticising billionaires in the presidential race in front of Michael Bloomberg in Compton, Califronia. The former New York mayor skipped the first caucus in Iowa and instead campaigned in California on 3 February Reuters

“The Berniebro solemnly posts links to his Facebook wall that night: Here is the focus group which said Bernie won the debate. Here is an online poll that said the same thing. Here is an online CNN poll that also declared his victory.

“The Berniebro knows a secret: The only reason you, and every other Facebook user, haven’t supported Bernie yet is your own willful ignorance.”

The term soon caught on. It was the subject of much chatter during Sanders’s 2016 campaign, and it’s now returned with a vengeance for his second run at the nomination – which, unlike in 2016, he now looks well placed to win.

Who does it refer to?

The term’s original definition is quite narrow. It refers to a subset of Sanders supporters, particularly those active online, who are so ardent in their support as to border on the obsessive.

As the name suggests, these are stereotypically young and white college-educated men, given to pouncing on anyone or anything who says or shares anything critical of Sanders – and indeed, of anyone who supports or votes for him.

This is something Meyer made sure to point out in his original piece: “The Berniebro is not every Bernie Sanders supporter. Sanders’s support skews young, but not particularly male. The Berniebro is male, though. Very male.”

This kind of behaviour among politicised progressive young men has been identified before. Back in 2008, the writer Rebecca Traister described a tribe of men: the Obama boys, whose fanatical support of Barack Obama in the Democratic primary included a detectable sexism against Hillary Clinton that bordered on the vicious.

“I was getting e-mails from men I didn’t know well,” she wrote, “who approached me as a go-to feminist to whom they could express their hatred of Hillary and their anger at her staying in the race – an anger that seemed to build with every one of her victories.”

Why do a lot of people find the term offensive?

For many reasons.

Firstly, many Sanders supporters dismiss the term as a lazy catch-all for the highly motivated and effective Sanders movement, and its overuse often ignores the diversity of Sanders’s movement.

The Sanders coalition is far more than simply a small group of fanatical white college men. In fact, in this year’s primary contests so far, Sanders has won a higher share of those without degrees than of those who do have them. He also appears to be doing noticeably well among Latino voters.

It can also obscure what support he gets from black voters – something challenged via hashtag in 2016 (#BernieMadeMeWhite) and now 2020 (#BernieBruh).

The campaign itself pulls no punches pointing this out. As national press secretary, Brihana Joy Gray, put it: “The ‘Bernie Bro’ smear is racist erasure. Use it, and you’re complicit. It’s that simple.”

Many supporters angry at the term say it mocks their passion for the things Sanders stands for, writing them off as obsessive fans when they’re actually motivated by deep moral commitment to specific principles.

This speaks to a more philosophical question about political intolerance.

Some Sanders supporters, and the “bros” in particular have developed a reputation for deep intransigence, and for putting devotion to the cause Sanders stands for ahead of defeating Donald Trump. After Hillary Clinton won the nomination in 2016, some vociferous Sanders supporters turned up at the Democratic convention to boo her.

Again though, “some” is the operative word. It’s simply not possible to quantify exactly how many Sanders supporters do things like this, and there’s no evidence that the vast majority of people who have voted for him – or intend to – have any inclination to behave this way.

Most of all, though, many Sanders supporters reject the idea that they and their movement are any more given to or guilty of harassment and bullying than supporters of other candidates. There are even those on the left who’ve questioned whether the phenomenon exists, suggesting that the “Bernie bro” is a spectre cynically conjured up by pro-Clinton journalists.

What is true, however, is that examples of Sanders supporters behaving badly are not hard to find.

How is it associated with allegations of harassment?

The behaviour for which Bernie bros and hardcore Sanders backers more generally are criticised goes beyond garden-variety mansplaining. Journalists, political officeholders and party workers have described receiving highly personal, co-ordinated group attacks when they’ve criticised Sanders in writing or in public.

Journalists who’ve recently incurred the wrath of the bros include The Atlantic’s Edward-Isaac Dovere, who published a piece detailing how Sanders considered running against Barack Obama in 2012 and had to be talked down by the Democratic establishment.

He soon found himself under siege.

“Write a story that some Sanders supporters decided they didn’t like, get 1,800+ spam text messages the next evening from fake list sign ups landing in the space of about 5 minutes.

“I’ve written a lot of stories about a lot of people in politics that have made a lot of people uncomfortable, but the way Sanders supporters react is unlike anyone else.”

After he described what had happened, others recalled similar incidents.

Others have experienced trouble offline. In the run-up to the Nevada caucuses, police were repeatedly called to disturbances outside the homes of Democratic officials and lawmakers caused by Sanders supporters with bullhorns.

And uncomfortably for the campaign, there have even been incidents involving staff. Ben Mora, a regional campaign field director in Michigan, was recently fired after tweets came to light in which he mocked rival candidates, their staff and their families. Among other examples, he captioned a picture of himself wearing an “Iowa for Bernie” shirt and carrying campaign flyers with the words “Spent the day cyber bullying women IRL”.

The journalist who exposed Mora’s behaviour, Scott Bixby, soon found himself subjected to online harassment from people claiming to be Sanders supporters themselves.

These are just a few examples of specific incidents involving Sanders supporters – but they are among a few that have been used to put the campaign under pressure to act.

What are the other candidates saying?

Sanders’s rivals have lately been hammering him hard for supposedly failing to rein his supporters in.

Billionaire former New York mayor Michael Bloomberg in particular has been up in arms, even running an ad featuring a slideshow of abusive and threatening messages saying other candidates are “going on lists” and telling others to “vote Bernie” or “bad things will happen”.

Also criticising Sanders is Elizabeth Warren, who became the subject of the #WarrenIsASnake hashtag at the end of last year when she said Sanders had told her a woman could never be president.

During a TV debate with the other candidates just before the Nevada caucuses, he was called on to account for recent incidents, including sexist slurs against female candidates and abuse directed at members of a union that was campaigning against him.

Pete Buttigieg, who later dropped out of the race challenged Sanders about the problem head on: “I think you have to accept some responsibility and ask yourself what it is about your campaign in particular that seems to be motivating this behaviour more than others.”

What has the Sanders campaign said?

In their efforts to disown certain supporters’ behaviour, Sanders and his campaign have made various different statements.

“We have over 10.6 million people on Twitter, and 99.9% of them are decent human beings,” Sanders said at the Nevada debate. “If there are a few people who make ugly remarks, who attack trade union leaders, I disown those people.”

Pointed out that plenty of surrogates for his campaign have been attacked as well, Sanders seemed to draw a line: “Our campaign is about issues … it is not about vicious attacks on other people.”

Meghan McCain challenges Alexandria Ocasio-Cortez on 'misogynistic' Bernie Bros

When asked to weigh in on talk show The View, Sanders surrogate and progressive hero Alexandria Ocasio-Cortez blamed the often toxic culture of the internet in general for the behaviour of certain Bernie bros. Co-hosts Meghan McCain and Whoopi Goldberg, however, said that Sanders hadn’t gone far enough to condemn the abuse given its prevalence and seriousness.

Sanders himself, however, has offered other explanations for what’s going on online. “In 2016, Russia used internet propaganda to sow division in our country, and my understanding is that they are doing it again in 2020,” he said in a statement. “Some of the ugly stuff on the internet attributed to our campaign may well not be coming from real supporters.”

But as Andrew Feinberg has reported, many on the left who have found themselves on the receiving end of supporters’ abuse absolutely consider the campaign to have played a part – whether by simply setting a tone of grievance against the establishment, declining to take action against known culprits, or even, in the case of some staff, by participating in it themselves.