DAN HODGES: Labour have maxed out on Left-wing voters so now they have a new target: Reform supporters

'Until now the strategy has been to squeeze the Greens and the Lib Dems, and that's been successful,' a senior Labour strategist explained to me last week. 

'But now there basically aren't any more to hoover up. They've hit their base. So the plan is going to have to change.'

This assessment is based on an analysis of Labour's private polling. But the evidence to support it is readily available in the public polls. 

According to the latest aggregator from Election Maps UK, support for the Greens has plunged to 9.1 per cent, precisely the same level it was at when co-leaders Carla Denyer and Adam Ramsay handed over to Zack Polanski in September 2025. 

Meanwhile, Sir Ed Davey and the Lib Dems now languish on 9.3 per cent, a full 3 per cent down on the 12.2 per cent they secured at the last General Election.

So the Prime Minister's decision to tack Left, and reunite the significant block of progressive voters disillusioned by Sir Keir Starmer's accursed premiership, has worked brilliantly. Too brilliantly.

'We've maxed out on Left-wing voters,' a minister conceded to me. 'We can't realistically expect to secure anything extra from hammering Polanski or flirting with Davey. We're going to have to broaden the appeal now.'

Prime Minister Andy Burnham during a visit to the Siemens Rail Technology Centre (SRTC) of Siemens Mobility near Chippenham, Wiltshire

Reform leader Nigel Farage announces the appointment of former Royal Air Force (RAF) Wing Commander Angus Macintyre as the party's new Shadow Armed Forces Minister

Within the Cabinet there is a growing belief among a number of senior ministers that Burnham is going to have to change course. 

And that if he wants to build a large enough cushion to justify calling an election before 2029, he is going to need to begin to reach out to Labour-leaning elements of Nigel Farage's own wavering support base.

They have been bolstered by data presented by Burnham's political director Hayden Munro, who believes as much as 5 per cent of Reform's current poll rating is potentially up for grabs.

'Hayden thinks there's a small but significant chunk of Reform support who could potentially switch directly to us,' another Labour insider reveals.

'But that would require a specific offer. And it would have to be different from what we've been presenting so far.'

There are three specific areas the Cabinet believe the Prime Minister should start to prioritise. One is immigration. 

Though most of the headlines last week focused on the watering-down of elements of Shabana Mahmood's new rules for migrants seeking to settle in the UK, it still represented a major toughening of the regulations.

The default period of a five-year wait for residency for most migrants inherited from the Tories was extended to ten years. 

For many of those arriving by small boat, it was extended to 30 years. And settlement will be denied completely for those with a criminal record or insufficient English.

But there was frustration among some ministers that No10 appeared to soft-pedal the announcement.

'There was some hardcore stuff in what Shabana announced,' one Cabinet colleague claimed. 

'But they weren't prepared to push it. It was all about how Andy had told her to row back on care workers.'

In the next few weeks, the Immigration and Asylum Bill returns to the Commons. 

It contains measures that are making a number of Labour backbenchers decidedly squeamish, especially on reform of the asylum appeals system, Article 8 of the Human Rights Act and modern slavery protections. 

But those who want to see Burnham reaching out to soft Reform voters are urging more robust support for the proposals from Downing Street.

'We can't have any more flip-flopping,' one MP in a marginal Red Wall constituency told me. 'Andy has to put his authority behind this. He needs to own these plans, not try to hide behind Shabana.'

A second key area is the environment. As The Mail on Sunday has reported, Burnham has been persuaded to give the green light to the opening of the Rosebank oil field, in opposition to protests from environmentalists inside and outside his Cabinet. But other key decisions remain on his desk.

One relates to the proposed expansion of Heathrow Airport. This is strongly backed by Transport Secretary Heidi Alexander, Chancellor John Healey and Business Secretary Jonathan Reynolds. 

At last month's Cabinet away day at Chequers, Alexander used her 30-minute slot with the Prime Minister to lobby hard for a swift decision approving the new development. 

But she is thought to face significant opposition from Energy Secretary Miatta Fahnbulleh and Foreign Secretary Ed Miliband, both of whom have aligned themselves closely with the Green lobby.

A further crunch point relates to plans to develop huge data centres and accompanying solar farms required to drive the expansion of the new AI technology. 

Again, this is strongly supported by Reynolds and Healey, but faces significant national and local opposition, which is alarming some of Burnham's advisers.

As one minister framed the argument currently splitting the Cabinet: 'We can't let ourselves become prisoners of the Net Zero lobby. 

'Ed and Miatta are zealots on this stuff. We need a more pragmatic approach. We can't build our entire strategy on trying to steal votes from Polanski. Especially when he's imploding anyway.'

A final major area of contention is defence, and the pledge to increase spending to 3 per cent of GDP by 2030. 

In the Budget, John Healey – who resigned over the matter when he was Defence Secretary – swerved the issue, committing to meeting the target while refusing to explain where the cash was coming from.

But a number of his colleagues believe it will not be possible for Labour to enter an election without a clearly costed commitment.

'We have to meet 3 per cent,' the minister told me. 'If we don't we'll be exposed on defence, and that's always been our Achilles heel. The Tories and Reform will hammer us into the ground if we don't.'

The polls indicate the Burnham bounce is still defying gravity. And there was relief within the Cabinet that the Budget landed safely, with both the public and the markets responding positively. 

But there is also mounting concern among ministers that the Prime Minister does not have the flexibility to recognise his 'Lean-Left' strategy has now run its course.

'Look at last week,' one complained. 'The message discipline was awful. The focus should have solely been on the Budget.

'But No 10 were jabbering on about Brexit and slavery reparations.'

The Prime Minister has run out of Left-wing voters. If he doesn't find some new ones, the muttering within his Cabinet is going to become louder by the day.