I think this would give them enough to be an opposition, not so different from 1997. It's how effectively they try to see off the far right that will be the key
I fear they'll just unite and then that would give them a potential majority but I would hope that they'd lose enough centre right people in disgust that they couldn't win. Lessons of France, Italy etc may suggest this is overly optimistic though
I think what's heartening to me is that the backlash is severe - and it's now Labour's to lose in the next cycle.
i.e. the right needs to come left to pick up the people they lost, which will hopefully blunt some of the extremism