What he [Bernie Sanders] does next will really determine whether he is blazing a trail that others can follow into office, or whether he is an exception to the rule.

Elizabeth Warren is, I think, a great demonstration of the kind of movement-oriented model-wielding power from within the Senate. Over and over, she's rallied tons of people to battles that they don't normally get involved in.

I think changing the Democratic Party platform [at the convention] is a great place to start. It should include expanding Social Security, a $15 minimum wage, and breaking up too-big-to-fail banks on Wall Street - among other Sanders priorities.

The most important thing will be building a bench of powerhouse progressives in elected office and in the next administration. [Bernie] Sanders has an enormous spotlight that he can shine on champions that are following the Sanders path of really building from the left.

An organization is great if you have a clear vision to be able to make it powerful. If you don't, an organization can kind of sap energy that could go elsewhere.

What he [Bernie Sanders] does next will really determine whether he is blazing a trail that others can follow into office, or whether he is an exception to the rule.

There is a question as to whether these rallies [2016] are going to stop in the fall. I think they should continue. They are a tremendous display of energy but also a source of energy, because people come out of them ready to fight.