If the Makerfield MP is to be our next PM, he needs some immediate and memorable cost of living policies to avoid his predecessor’s fate

Pause here before we rush headlong into the turbulent future. Stop and inhale last week’s rare political triumph, revel in the sunshine of cheery optimism. It was a precious but unfamiliar sensation when life on the progressive side of politics in Britain is so often a litany of hopes dashed and disappointments.

Andy Burnham’s comprehensive victory in the Makerfield byelection, surpassing expectations, was a precious moment. He demolished £5m-Nigel Farage’s party of loathsome Reformers, whose every election candidate seems more repugnant than the last. Hostile hard-right politics in Britain needs defeating time and time again, every time nativists and hate-stirrers – from Enoch Powell to the BNP – erupt in our politics.

In just 48 hours, the PM has felt the weight of political gravity and shifted from initial adamance he would fight on

Rapid change has hardly been unusual in British politics in recent years, but the change of tone from Keir Starmer and his supporters in just 48 hours has been striking – and appears to chart the shift in his position on his own future from one of defiance to glum acceptance.

While PM’s desire to fight was strong, time with his inner circle at Chequers sharpened his sense of the inevitable

On Friday, as the dust settled on Andy Burnham’s thumping victory in the Makerfield byelection, Keir Starmer was in defiant mood. “I have said repeatedly, I am not going to walk away,” the prime minister said, adding: “Let’s pull together as a party and a movement.”

Just 48 hours later, one of his most loyal ministers was on the BBC sending a very different message. “I don’t want to come on here and be delusional that there is no process, there are no forces at work which are challenging the prime minister as leader – that is clearly the case,” said the business secretary, Peter Kyle.

Business secretary says PM spending the weekend ‘making time to reflect on the political realities’ he faces

• Keir Starmer expected to announce departure as prime minister on Monday

Some commentators have said Andy Burnham is just a better communicator than Keir Starmer, but have questioned how different he is on policy.

The Guardian’s policy editor, Kiran Stacey, has helpfully looked at the political projects a Burnham government would likely pursue in this useful explainer: