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The constituency of Makerfield has been a Labour safe seat for generations, but in the May elections, Reform UK won nearly every seat that was up for grabs at the local council.
So how much of a gamble is it for Andy Burnham to try to stage a Commons return here?
In his favour is his personal popularity in Greater Manchester and the fact he grew up in the area. Against him is the momentum of Reform and the fact that Makerfield hasn't benefitted from some of Burnham's key policies as mayor of the city.
To discuss his chances, Niall speaks to Rob Ford, professor of political science at the University of Manchester.
Have you got a question for Niall? Email the show - why@sky.uk
(c) Sky News 2026: Why winning Makerfield by-election may not be so easy for Burnham
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