Bernie Endorses
By 
Senator Bernie Sanders endorsed Joseph R. Biden Jr. as the Democratic nominee for president on Monday, adding the weight of his left-wing support to Mr. Biden’s candidacy and taking a major step toward bringing unity to the party’s effort to unseat President Trump in November.
In throwing his weight behind his former rival, Mr. Sanders is sending an unmistakable signal that his supporters — who are known for their intense loyalty — should do so as well, at a moment when Mr. Biden still faces deep skepticism from many younger progressives.
The two men appeared via live stream on split screens — each on each other’s live streams — talking to each other. “We need you in the White House,” Mr. Sanders said to Mr. Biden. “And I will do all that I can to make that happen.”
My understanding is that this was considerably eased by the fact that Bernie genuinely likes Biden, and that Biden treated Bernie cordially when he arrived in the Senate. Relationships, it seems, matter to politics