While there are, obviously, big structural forces at play in Labour’s defeat, some of the tactical decisions that Starmer’s team have taken have not helped either. First, they chose an MP defeated at the last election — and one who had tried to stop Brexit — as their candidate. This gave the Tories an opening to talk about that issue. Second, they decided to hold the by-election on the same days as the Tees Valley mayoral contest, allowing the relatively unknown Tory candidate to link herself to Ben Houchen, the hugely popular Tory mayor.
The problem for Starmer is that the building blocks of Labour’s traditional electoral coalition are moving ever further apart from each other. If Starmer moved further to try to win back support in seats such as Hartlepool, he would risk alienating Labour’s metropolitan base in cities such as London and Bristol — in those places, Labour is expected to win the mayoralties at a canter.