If this happens, a lot of Bernie supporters will either not show up at the polls, or will vote for a third party candidate like Jill Stein was in 2016.
Interesting box the Dems have painted themselves into.
1) Nominate Bernie and have a huge negative impact on the down ballot candidates when people who won't support a socialist don't show up at the polls
or
2) Don't nominate Bernie and have a huge negative impact on the down ballot candidates when the Bernie supporters don't show up at the polls