Great Grimsby and Cleethorpes on the Humber estuary is a constituency that stitches together a town that once laid claim to being the biggest fishing port in the world at the height of the industrial revolution and the more Conservative-leaning seaside resort and rural villages around Cleethorpes.

This new constituency was a bellwether seat in the 2024 general election, sitting at the heart of the “red wall” in Brexit-backing Lincolnshire. A key seat in the Labour-Conservative battleground, this is a place Sir Keir Starmer had to take back on his path to power. And he did.

It was a big symbolic win for Labour as the party took back Great Grimsby, which had been Labour since the Second World War but flipped to Boris Johnson’s Conservatives in 2019 and took the more rural and affluent Cleethorpes too.

But the bigger story on the night was that the Labour vote was as shallow as it was wide, and what I mean by that is Sir Keir’s massive working majority of 165 seats was won on the lowest vote share of any government since the Second World War.

As landslides go, this one was built on particularly shaky ground. The victory was as much the story of a rejection of the Conservatives and the rise of other parties as a tale of a country embracing Labour.

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Millions of votes went to Reform and the Liberal Democrats, as the Conservatives suffered their worst-ever election defeat. Nigel Farage’s Reform party won around 14% of all votes cast, returned a record five MPs to parliament and came second in more than 100 others, 89 of which were Labour seats, including Great Grimsby.

Ask those in Number 10 and they are all too aware that the realignment towards the populist, nationalist right – as seen in other Western democracies – is a very real prospect here, with those leaders – not least Nigel Farage – emboldened by Trump’s emphatic victory in the US.

With Germany and France both facing a real threat from the far right in national elections in 2025 and 2027 respectively, Sir Keir could soon find himself as the last major centre-left leader standing in the continent.

Sir Keir also is under no illusion that he will face the wrath of voters should he fail to deliver on the promises he made in the July general election, and the budget was the downpayment if you like on those pledges as we finally saw the true contours of this Labour government. This was a budget as historic and hefty in its tax and spend plan for Britain as the Labour’s manifesto was fiscally vague. At its heart, a huge investment in public services, and in particular the NHS, and front-loaded to the first two years of this parliament.

That’s the plan, but how is it landing? During the general election campaign, Great Grimsby and Cleethorpes were Sky News’ target towns. We wanted to see the election through the eyes of those voters both sides desperately needed to win and the centrepiece of that effort was our leaders’ event at Grimsby Town Hall, in which an audience of undecided voters put their questions to Sir Keir and Rishi Sunak. On the night, a snap poll by YouGov gave Sir Keir the win by a margin of two to one.

After the budget, we returned to Grimsby to see how it, and the new government, had been received with three of those voters – Amy, Sharon and Caiman – who asked questions at the Sky News Battle for Number 10 election event.

It has, after all, been a difficult start for the Labour government, and the budget wasn’t exactly as advertised in the run-up to the election. I wanted to find out how this trio thought Sir Keir was doing.

‘It’s felt chaotic’

Two of the big themes of the show were around trust and tax. Sharon, a lifelong Labour supporter who works in the care sector and lives in Grimsby, had really wanted to know how Sir Keir intended to “improve outcomes” for disadvantaged residents and if the now prime minister really wouldn’t put up taxes in order to invest.

Sharon, watching her question back, agreed that it had been the right question to ask and told me that, far from being protected as a “working person” in the budget, she thinks she’ll be indirectly taxed as employers pass on the £25bn of national insurance tax hikes either to employees through lower pay or consumers through higher prices at the shops.

“I’m hoping it comes off, because it feels like a gamble, because he said it’s all dependent on growth,” she said. “I did vote Labour, I’ve always voted Labour, but the Labour I’m seeing so far – there’s been so much – it’s felt chaotic.”

Amy, a former chair of her local Conservative party, couldn’t bring herself to vote for Mr Sunak and ended up voting Liberal Democrat in an election where she said trust was her main concern.

During the leaders’ debate, she told Mr Sunak that actions taken by his government around “partygate” and his decision to leave the D-Day celebrations early had made her feel ashamed and left the Conservative party’s reputation shattered.

She told me that trust was still her big issue four months on from the general election: “[Trust] is a huge issue here. I don’t think this government has covered themselves in glory.” And when it comes to Sir Keir and the budget, Amy said the prime minister talked about bringing growth to the country “which is absolutely what is needed”.

She added: “How has he done that? By, you know, putting the burden on businesses to grow. That’s just not there.”

‘I feel he’s still a robot’

For Caiman, his was the question that foreshadowed concerns plaguing the early days of Sir Keir’s premiership – that this was a prime minister lacking a human touch and struggling to give voters a vision to justify the tough choices he was making.

Caiman said that while he’d once liked his genuineness, the Labour leader had “formed into more of a politician than the person that I would have voted for to run the country”, telling the prime minister: “You seem more like a political robot.”

Four months in Caiman was still of that view: “Anyone that’s human who has a heart wouldn’t have taken the winter fuel allowance pensioners. I feel like he’s still a robot.”

Of the budget, he said: “It almost feels like a bit of a punishment rather than what we all know, that we need to chip in for our public services. But it’s back to the point about the messaging. Nobody’s laid that out for the ordinary person.”

I was left in no doubt from this trio that the jury’s out on the new government. When I asked them to mark the first fourth months out of 10, Amy gave Sir Keir five, Caiman gave him a four and Sharon, once the loyal Labour supporter, told me: “I’d rather not say at the moment.”

Even the local MP, Melanie Onn, who lost her seat in 2019 but won it back for Labour in 2024, admits she was surprised by the scale of the Labour budget. “I was [surprised], which I was told to stop keep saying that.”

But this was a “bold budget” that she welcomed. “We need to be bold and we need to do everything that we can to try to turn things around as quickly as possible and that means investment, so for me, I was really pleased to see that there was an acceptance that you can’t growth the economy without investing and getting things like our public services back on track.”

‘It’s been a bit of a rocky start’

It matters all the more for Ms Onn, who is well aware that her victory was partial. Yes, she won the seat back, but Reform ran well in not just her seat but dozens of other red wall places that had been traditionally Labour but where voters are now looking for a new political home.

“I think that there was a sense of people who had voted for the Conservatives in 2019 looking for a new home,” she explained. “A lot of those people, they’d given Boris Johnson and the Conservatives a go and that hadn’t really worked. And so they were going to go for Reform, who, of course, making lots of lots of promises that they knew really that they didn’t have to stand up.

“For anybody who perhaps wasn’t convinced by Labour this election, because it’s fair to say that not everybody was, we asked them what their big issues were and they said the NHS and immigration and Reform had a response on those two issues.”

For Ms Onn, the budget now sets the direction for a government that has put cutting waiting lists at the heart of its early years with a £25bn investment in the health service in the next two years.

“You’d be blind not to say it’s been a bit of a rocky start to the Labour government. I think that really we we’re waiting for the budget. I think it sets a very clear direction and we’re going to work really hard to turn the country around and deliver the change that people want to see.”

Her piece of the red wall has been won back, but never before has a political landslide stood on such shaky ground. Sir Kier and his chancellor are gambling that his big budget will, in time, pay off and see off the populist threat by persuading voters about his promise of change.