Nobody would expect a football team to concede before the game is over, no matter how impossible the hope of overtaking the other side. The same should be the rule in a political contest. Play to the whistle.

The contests that really matter are the ones for Congress and Senate. As the last eight years has shown, the gerrymandering that means that a country consistently voting Democrat is liable to be saddled with Republican legislatures means that a Democrat president is largely powerless.

The hope must be that Trump will so screw up the whole Republican that enough Democrats will be elected to compensate for the bent electoral system, and that the momentum of the Sanders campaign will mean that the Democrats elected would largely represent that momentum.