Stephen Kent, a spokesman for the D.C.-based public relations firm Young Voices, told me libertarians like him have “an opportunity to drop ‘classical’ from the way we describe our liberalism and just step in as the champions of liberal thought and the open society.”

Biden, even to his left-wing former rivals, remains someone who can sell a vision of liberal gains while promising a return to “normalcy” in our politics.

Bernie Sanders could win the White House, but he would have to get real about America’s right of center populist leanings.