Bernie Sanders has the internet to thank for invigorating his energetic, youth-driven, grassroots presidential campaign. But the internet has also created a host of problems for Sanders’s campaign, problems also known as the Bernie Bros.

The Vermont senator has tried to distance himself from the anonymous trolls who swarm and attack anyone remotely critical of his campaign. Sanders denounced the “vicious” tactics some of his online supporters have used after they went after members of Nevada’s Culinary Union. And he has since tried to downplay the significance of his most aggressive keyboard warriors.