Andrew Prokop in Vox:
And what, exactly, does he mean by that?
On its surface, the concept is simple: Sanders wants to organize and mobilize the people against the powerful — specifically, corporations and the wealthy. He argues that by building a movement among average Americans, he'll be able to win elections, defeat special interests, push liberal reforms into law, and build an economy that works for everyone.
But when you drill down into the details, Sanders's hoped-for political revolution is more complicated than that — and more interesting.
For one, it's a contested theory about the best way to advance progressive policies. For another, it's an electoral argument about how the Democratic Party can expand its appeal among white voters and change the existing partisan math. It's a case that the system is so broken and corrupt that extreme measures are needed to shake it up. And it's a usually implicit, sometimes explicit critique of President Obama and his party.
More here.