Jamie Reed, the Corbynsceptic Labour MP for Copeland, has accepted a job offer at Sellafield, and will quit the Commons at the end of January, triggering a by-election in February.

The circumstances could hardly be less favourable for Labour. We’ve seen in the Richmond and Sleaford by-elections that the party is shedding both Remain-inclined voters to the Liberal Democrats and Leave-inclined voters to the Conservatives and Ukip.

What much of the commentary around various constituencies as “Brexitland” or “Remainia” is that even in places which saw the biggest landslides for one side or another, a sizable and potentially electorally decisive block of voters went the other way. Even Lambeth, the most Remain-friendly borough in the country, has a 22 per cent Leave vote, while Boston, its Leave counterpart, has a 25 per cent Remain minority.

In the case of Copeland – Leave won by thirty points, but that still leaves a third of voters who backed the status quo.

Put plainly, there is no seat where Labour is not potentially in jeopardy from both the parties of the right and the Liberal Democrats while Brexit remains the animating political issue. That Jeremy Corbyn is opposed to both nuclear power and the Trident submarines – major employers in the region - is, in these circumstances, rather low down the list of Labour’s problems in Copeland.

The party’s majority is just 2,564, though as ever, it’s more instructive to talk percentages where by-elections are concerned. Labour leads by 6.5 per cent. All that the Conservatives need to do is tread water and hope that the Liberals and Ukip can take just three points each from Labour.

As such, the Tories start as strong favourites to win the seat, with one minor caveat. The Labour leadership believe that when the conversation turns back to the economy, the Brexit polarity will fade, easing the party’s woes. The expectation is that the by-election will be held in February, when food price inflation could be beginning to make itself felt. Labour usually likes to hold by-elections as quickly as possible. It may be that, on this occasion, time is on its side.