Yeah but, Erik, there’s a big difference between liking Bernie more than Trump, and being motivated to knock on doors, donate, register voters, show up at the polls, convince your friends, etc. — all the volunteer tasks that go into the ground game required to win an election.
Voter turnout is everything for Democrats. If Bernie is perceived as pandering too much to white guys as he was during the primary (take for instance the much-discussed “Bernie Bro” phenomenon), he risks alienating the essential voting blocs of women and non-whites.
Just look at the millennial problem the Hillary campaign is struggling with. It’s not enough that young voters like Hillary more than Trump. Many don’t feel like Hillary has earned their vote. Bernie would face the exact same problem with demographics that his economic equality message doesn’t directly speak to.