TO which of the major parties is it most important to win the Hartlepool by-election.

Although we are only just at the beginning of what is being regarded as the most important by-election for 30 years, the result is too close to call. The bookies initially thought the Conservatives were slightly ahead, but the odds of moved a couple of points and now Labour is ever-so-minutely in front.

Boris Johnson’s Tories would love to steal the seat. If they don’t, it could show that their momentum, which has swept through the Tees Valley and County Durham, is beginning to stall now that Brexit is done.

But only a few years ago, the thought of Hartlepool having a Conservative MP would have been unthinkable – in the same way Sedgefield or Bishop Auckland having one was.

It has to be Labour which has most to lose if it can’t hold on to the seat. Jeremy Corbyn was very unpopular and Sir Keir Starmer has to show that the party is turning a corner.

On election night, there will probably lots of other results drowning out Hartlepool – Scotland and the London mayor, for example – but if Labour suffered defeat in such an established seat which it has to hold if it is to challenge Mr Johnson, it would be a big loss.