Not necessarily. If Sanders doesn't win on the first ballot (and he doesn't have enough delegates to do that), round two is a free for all. Plus Democrat delegates tend to be very loyal to the party honchos. If they're told never-Sanders, they will not pick him on the second ballot.
Bernie Sanders is next in line. Bernie has the most delegates behind Biden. 3rd is Warren. They have to go through them first.
Not necessarily. If Sanders doesn't win on the first ballot (and he doesn't have enough delegates to do that), round two is a free for all. Plus Democrat delegates tend to be very loyal to the party honchos. If they're told never-Sanders, they will not pick him on the second ballot.