Because it includes a full reimagination of the society, including more progressive proposals like free college and Medicare for All, they ask, ‘Why can’t you take the climate parts and leave out the other stuff?’ In the mind of the establishment Democrats, climate action is popular, but disruptive social action is not.

Are there ways this movement organizes or operates that are unique compared to other contemporary groups or social movements?

I think Sunrise has learned a lot from modern movements, including Occupy Wall Street and Black Lives Matter. What separates them, to me, from those groups are a couple things. They have a specific, tangible policy they’re pushing candidates on: the Green New Deal. They coordinate with other groups such as Justice Democrats and New Consensus to get their policy and politics message on one accord. And they’ve coincided with this progressive moment, so that they have champions on the national stage such as Representative Alexandria Ocasio-Cortez and Senator Bernie Sanders. That allows them to command media attention at any moment, as they did to put pressure on Joe Biden — as we saw in this episode of “The Weekly.”

What are the demographics of voters drawn to a progressively environmental platform?

The demographics are a great question. I’ll focus on race. While Sunrise certainly has a racially diverse leadership group, like Varshini Prakash , and allies, like Rhiana Gunn-Wright , their core base remains many young, white college students. At one rally we attended in Washington, on the campus of Howard University, a historically black college, the crowd was almost exclusively white. This is a challenge for them. To make an imprint in the primary, they need to diversify the coalition of people who care about the Green New Deal. Alexandria Ocasio-Cortez has made this a top priority, but it’s also why they believe that adding the social justice goals with the climate ones are so important.

The other piece of irony: The 2020 race’s most prominent moderate, Joe Biden, enjoys strong support from black voters.

Taking the view of the last 30 to 40 years, how successful have centrist Democrats been at the local, state and federal levels?

We presented two theories of what Democrats say they need to do in 2020 to win. Certainly the centrists have had their way for a while, and have experienced significant electoral losses using a model that tries to court more moderate swing voters. They point to the 2018 midterm election results, where the Democrats that helped take back the House in swing districts and statehouses in the Midwest were actually fairly moderate, even as the party’s left got significant attention.