Polls have closed in the crucial Makerfield by-election as Andy Burnham waits to see if voters have handed him a route back to Westminster to challenge Keir Starmer.

The Greater Manchester mayor has spent the past four weeks campaigning as Labour's candidate in the seat as he seeks a return to the House of Commons.

If he is successful in becoming Makerfield's new MP - with a by-election result due in the early hours of Friday - then Mr Burnham will quit as mayor and end his 9-year hiatus from Parliament.

His stated intention is to then try and oust the Prime Minister and 'change' Labour, with the 56-year-old expected to attempt to push the party to the Left.

A dramatic return to Westminster for Mr Burnham will bring fresh civil war to Labour, with an increasingly obstinate Sir Keir having so far defied calls from his leadership rivals and disillusioned MPs to step down.

Reform UK has mounted stiff opposition to Labour in Makerfield, with Nigel Farage's party intent on winning the consituency and dashing Mr Burnham's long-held ambition of becoming PM.

Mr Farage and Reform's candidate, self-employed plumber Robert Kenyon, have spent the last month urging local voters to 'vote Reform, stop Labour' in their efforts to derail Mr Burnham's bid for No10.

But Reform's campaign has been being hampered by the decision of Restore Britain, the hard-Right party set up by ex-Reform MP Rupert Lowe, to also stand in the constituency.

Prior to Thursday's vote, opinion polls had shown Restore splitting the Right-wing vote by a large enough margin to hand Mr Burnham victory in Makerfield.

Mr Farage used a polling day social media video to send a clear message to those thinking of supporting Restore, stressing that Mr Kenyon was the only realistic option to stop Mr Burnham from winning.

'What is clear is that if you vote for anybody else other than Rob you're effectively voting Labour,' he said.

In his own social media video on polling day, soundtracked by Manchester band New Order, Mr Burnham said: 'This is a change by-election.

'We left Westminster 10 years ago to build something different, something better.

'We worked on a place-first basis, rather than party first, problem solving rather than point scoring.

'We've taken that fight for people here, and I'll carry that fight forward if I am lucky enough to be elected as the MP for Makerfield. I'll take that fight as high as I can possibly take it.'

Sir Keir's challengers still want the embattled PM to set out a timetable for his departure from No10 himself, to avoid them having to trigger a bitter contest themselves.

Some are hoping that senior ministers will tell him at next Tuesday's Cabinet meeting that his time is up as he has become the most unpopular PM in history.

But Sir Keir remains determined to fight on and could try to shut down any discussion of his future around the Cabinet table, as he did last month despite dozens of his MPs telling him to quit.

He and his team insist he alone has the mandate to lead the country, less than two years after he won a landslide general election, and see no reason why he should give it up.

Sir Keir will not travel to Makerfield  - where an estimated 3,000 Labour activists packed the streets on Thursday in an unprecedented drive to get voters to the polling stations - should Mr Burnham win, as is usual the morning after a by-election victory.

Instead the PM will speak to broadcasters on a visit elsewhere and, although he is prepared to welcome his rival's victory, he will say that a leadership contest would be a dangerous mistake.

However if any of his challengers - who also include former Health Secretary Wes Streeting - does decide to trigger one by announcing they have the requisite 81 backers, he will take part in it and so try to cling on as Labour leader and PM.

One senior source told the Daily Mail: 'He will be clear that a challenge would be wrong for the party and the country. But if there was one he is ready to fight it.

'I don't know why Andy Burnham thinks he's got the right to a coronation just because he's won a by-election.'

Another insider said: 'He feels a sense of duty and is not going to walk away.'

The source said rival camps are desperate for Cabinet ministers to move first and tell Sir Keir he has to go, so that they are not seen as disloyal by starting the race.

They also questioned Mr Burnham's sense of entitlement but predicted he and his team would soon realise the scale of the challenge facing him.

'They're on a high, thinking they've won a by-election and now they're going to take No 10.

'But the reality of coming back to Westminster is going to hit them like a ton of bricks.'

Jockeying is already under way among senior Labour figures for a place in Mr Burnham's top team if he does take over.

Ed Miliband, whom the Daily Mail revealed could quit as Energy Secretary next week to trigger the coup that brings down Sir Keir, is widely expected to become Chancellor.

Louise Haigh, who was forced to quit as Transport Secretary after it emerged she had a historic conviction for fraud, has led the by-election campaign and could be made Health Secretary.

Anneliese Midgley, who was once an adviser to Sir Keir, would be Chief Whip in Mr Burnham's administration and his policing chief Kate Green has been tipped as his Chief of Staff.

Rachel Reeves, who is keen to remain Chancellor even in a new administration, warned leadership contenders not to risk changing her fiscal rules.

She told a conference: 'We got elected on the promise to return stability to the economy, and anyone who wanted to deviate from that will not be fulfilling the manifesto commitments.'

Even if Mr Burham does become PM, many expect his honeymoon period to be even shorter than the one Sir Keir enjoyed.

He will face calls to hold a general election as he will not be seen as having a mandate, while he will lack the money or tax-raising powers to implement the Left-wing policies backbenchers want, such as nationalising utilities.

'This PLP [Parliamentary Labour Party] is not scared of speaking out,' a source said.

Despite Sir Keir's insistence that he is not going anywhere, some still expect he will be forced to step down soon.

Resignations could take place in the coming days to pile further pressure on him, amid reports that 'trigger happy' ministers have been told to hold fire over the weekend.

Others want senior figures to use Tuesday's Cabinet meeting to talk the PM into resigning.

One source said: 'Over the weekend people who say privately Keir should go need to start saying that to him, or publicly.

'The fact is that he doesn't have the support of most of his Cabinet, his frontbench, the PLP or most of the country.

'The best way forward is to set out a timetable for future-facing candidates to debate ideas, rather than a bitter contest where it's a blame game for everything that's happened for the past two years.

'Keir will go either way but this way the agency is with him. Lots of people are hoping he will see sense.'

They added: 'Keir banned discussion of his leadership at Cabinet last month. This time they've got to insist and make their views known.'

The Makerfield contest was triggered by the resignation of Josh Simons as the local MP, who said he wanted to give Mr Burnham a chance to return to Westminster to challenge Sir Keir because Labour was 'imploding'.

Mr Simons gave up the constituency he won for Labour with a 5,000-vote majority at the 2024 general election in the wake of his party's meltdown following disastrous results in elections in Scotland, Wales and English councils in May.

'Labour needs to change and the whole Government needs to change,' he said last month.

Mr Simons has been touted for a top role in Downing Street, should Mr Burnham be successful in his bid to take over from Sir Keir.

During the by-election campaign, Mr Burnham finally admitted British politics worst-kept secret when he used a BBC Question Time special in Makerfield to confirm he would go for the top job if he won the seat.

'I can't do anything unless I'm lucky enough to get the support of people here,' he told the programme.

'But if I get your support, I would seek to represent you at the highest possible level and give this constituency maximum power and influence.'