It is possible for both Andy Burnham and Sir Keir Starmer to be right about the mathematics of the Greater Manchester mayor standing in the Gorton and Denton by-election.
Mr Burnham is completely correct that he – of all the possible Labour candidates in what could be a crucial by-election – stands the best chance of winning. The polling suggests that, without him, Nigel Farage’s Reform UK wins by six points. With him as the candidate, Labour win by four, it says.
The last thing Labour needs is another Reform MP in the northwest to join Runcorn’s Sarah Pochin, the last beneficiary of a by-election forced by a disgraced Labour MP from the northwest of England standing down.
But, on the other hand, Sir Keir is also correct. If Mr Burnham were to stand in the by-election and win, then he would be forced to step down as mayor of Greater Manchester. This would precipitate an election for the mayoralty as well.
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Labour had to ask itself the question whether it could win that mayoral election and probably came to the not-unreasonable conclusion that there is only one candidate who could win it for them. Yes – the very same Andy Burnham.
The reality is that any by-election or election now poses a serious risk for Labour with votes peeling away to Reform on the right and the Greens on the left.
Some polls have had Labour as low as fourth and fifth place and Sir Keir’s personal ratings have been dreadful, while Mr Burnham’s have been quite positive.
This is where the vague hope that Mr Burnham could be the only man to stop Mr Farage comes from. It may be true but a lot can happen to change people’s perception of a politician, especially if they get into No 10.
After all, it was only 18 months ago that Sir Keir was leading his party to an enormous victory and huge mandate. Now, it has all but evaporated.
In some ways, the question faced by Labour’s national executive committee was to decide which option was the least damaging: to lose a parliamentary by-election or to lose control of a mayoralty with a budget of billions and a vast amount of devolved power.
If Reform got its hands on the Manchester mayoralty, then whoever took that position could start to do some serious damage. Another Reform MP in parliament will get lost in a small group among 650.
That said, this was still only a secondary calculation to the fear that Mr Burnham would be in a position to replace Sir Keir as leader and prime minister in a bloodless coup if he won the by-election. He certainly has the numbers to do that among MPs and within the Labour Party membership.
Either way, the maths did not add up for Sir Keir and his supporters on the NEC – which is why Mr Burnham’s application had to be blocked.
