The DNC cannot allow Bernie to get their nomination. So, how will they cut his legs out without pissing off his followers?

They will go for a Brokered Convention.

The DNC has been without leadership since Dean was forced out. Bernie should never have been allowed into the debates in 2016 as he was not a Democrat. But it was also the fault of the DNC choosing Hillary as the only candidate for office. Does anyone even remember who was in those first few debates?

The DNC won't be able to give the nomination to someone else without angering the Bernie Bros.  The DNC may figure it doesn't matter for 2020 since Trump will be re-elected.  

Bernie reminds me of Scrooge. I expect him to mouth "Bah humbug" at any moment during the debates. Keep in mind, the percentage of moderates combined outnumbers Bernie's percentage. So most of the populous are in favor of a moderate candidate. Once a single moderate candidate remains in the running they should outnumber Bernie in the polls and primaries.

The DNC won't need to do a thing. The people will do it for them.

Maybe they'll manufacture a scandal this time around.

You don't suppose they'll kill the poor old codger do you?

(:

The Left is united this time. Americans are sick and tired of Trump's corruption.

Never look a dead donkey in the mouth.