The latest data from the Pew Research Center, proves both Penn and Warren correct. Democrats have moved dramatically leftward since the 1990s on issues like the social safety net, immigration, and race relations. On those issues, the so-called Warren wing represents the mainstream of Democratic opinion.

But, Penn is also correct in arguing that white, older working class Americans are not coming along for the ride. However, it’s also clear that it’s going to be very difficult for a Democrat to win the nomination of his/her party on anything but the Warren platform.