Sure, but their support is brainwashed into the belief that Magic Grandpa will storm to victory as soon as the people get a chance to vote for him. His whole schtick is predicated on this idea, in fact. Take away that key plank of magical thinking by showing you're scared to face the tories in an election and the whole thing might come crashing down.
Be interesting to see what Labour does if they get whitewashed in the GE. The membership rule changes allowed the unions to take control of the party hence thieving blockheads like Ian Lavery and communists like McDonnell in their positions.
But even if they get hammered, the unions will still be in control. Not sure they would allow a return to *New Labour* but even they might realise how fruitless it is to persist with the red flag brigade. Maybe. A more palatable version of Corbyn, if such a thing exists?
Let's hope we find out.
If the defeat is bad enough (esp if Brexit Party hit the northern heartlands hard), it could reduce Labour to a relative rump and get rid of a lot of moderate MPs, which, while it would make the party more politically coherent, would also make it smaller and with less broad appeal. It could thus carry on being mentally leftist while the LibDems or a new party hoovered up the moderate supporters.