So it qualifies as a significant development that Sanders chose to endorse Joe Biden in April, less than a week after ending his own campaign. In 2016, by contrast, he waited until July to endorse Clinton. Sanders’s decision this time seems to reflect three things: his desire to help defeat Trump; the danger of voting during a pandemic; and a genuine personal affinity between Sanders and Biden.

Endorsements aren’t all powerful, and no doubt some Sanders voters will still choose to stay home or support Trump. But in all likelihood, fewer of them will do so this year than did four years ago, especially if Sanders campaigns energetically for Biden.

And Biden is likely to need those voters.

In a new analysis, Nate Cohn — a Times polling expert — argues that the head-to-head polls showing Biden with a consistent lead over Trump may be overstating Biden’s strength. The polls are often national polls, and Trump looks somewhat stronger in swing states like Pennsylvania, Michigan and Wisconsin. And many of the polls cover all registered voters, including those who are unlikely to vote, and unlikely voters lean toward Biden.

All of which suggests that Sanders voters may once again play a critical role.

For more …

David Axelrod: “This quick, warm and unambiguous endorsement from @BernieSanders is a huge and important boost for @JoeBiden. Without papering over their differences, the two projected a united front. Each handled this well.”

Ezra Klein, Vox: “Biden is acting less like a candidate than a party leader, less like one side of an argument that will be settled by his victory and more like a legislator who recognizes the only way to [win] is to make real, serious concessions to his colleagues. He’s not asking the left to ‘bend the knee’ and accept his victory. He’s inviting them into coalition and offering concrete concessions and avenues of influence in return for their participation.”

Jennifer Rubin, Washington Post: “The cessation of hostilities was made possible, in large part, because of the friendly relationship between the two, and because of the Biden camp’s extreme solicitousness in refusing to call for Sanders to get out of the race.”

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