December 12, 2018, is a day James Johnson will never forget.

Having secured a job in Downing Street aged just 24, his career at Number 10 was potentially just hours away from being over.

His boss, the Prime Minister, was facing a confidence vote triggered by 48 of her own MPs.

"It was very tense," the former Folkestone schoolboy admits.

"These things can swing very quickly. And it wasn't just about winning - it was winning decisively."

After a nervy day, Theresa May did claim victory - by 200 votes to 117.

It meant another confidence vote couldn't be triggered for at least 12 months.

But there was no sense of relief for the special advisers in Number 10.

"We had the Brexit deal to pass," says James.

And as the PM's chief pollster, he knew how difficult that would be.

Not only were a large chunk of Tory MPs opposed to it, so was the majority of the public. Meanwhile, Mrs May's approval ratings were plummeting.

James' task was to deliver this rather ominous message in meetings with a Prime Minister famous for her "death stare".

But he never tried to sugar-coat the often unpalatable truth.

"The thing I've learned about (being a pollster) is you have to be as honest and as frank as possible," James explains.

"The Prime Minister was like any professional and would take it constructively and work out what to do with it.

"One of the undocumented things about that period is that while at the end her approval ratings were very low, in the focus groups you found people had a grudging respect for her."

After the Conservatives lost their majority in the 2017 snap election, Theresa May faced a constant barrage of attacks - from Brussels, Jeremy Corbyn and her own MPs.

During her Tory conference speech that autumn, she suffered a coughing fit and even the letters on the wall behind her fell down.

As the pressure grew, James remembers one senior colleague saying: "This is one day at a time at the moment and it could all come crashing down at any moment."

But although she was carrying so much weight on her shoulders, the Prime Minister didn't show it inside Downing Street.

"One of the really interesting things about that time is that she was so nice and friendly in person," says James.

"She was very funny. She has a self-deprecating sense of humour which I think people saw with the dancing before her conference speech (in 2018).

"You felt completely at ease. There was a good atmosphere.

"You felt you could pipe up and say something."

The daily drama inside Downing Street was a world away from the quiet village of Lympne, near Hythe, where James grew up.

He fondly remembers "fantastic" Lympne Primary School and its "brilliant teachers", who helped 23 children in his class get into the local grammar schools.

At the Harvey Grammar in Folkestone, he credits inspirational teachers for going the extra mile and encouraging him to apply for Oxford.

While James had always wanted to go to university, his parents didn't pressure him to take any particular path. His dad ran his own insurance firm - after starting out at KFC - while his mum worked for Saga.

But after attending an open day at Brasenose College - where David Cameron studied - James was determined to secure a place.

He later changed his course from English to History and Politics - and his enthusiasm for the world of Westminster even saw him take a cardboard cut-out of then Communities Secretary Eric Pickles on a tour of America.

After uni James won a place on a management consultancy graduate scheme at Deloitte.

But he again switched paths - slashing his salary in half to become a researcher at the New Schools Network charity.

Through this job he started attending meetings at the Department for Education and in Parliament and building up contacts.

In September 2016 he was asked if he was interested in a job in Downing Street and grasped the opportunity.

Working at Number 10, James would jump on the tube from his flat in Stockwell to be ready for the first meeting of the day at 8am.

"You get to walk down the street every day," says James. "You get to knock on the door and awkwardly wait for someone to open it - or let Larry out."

Once past the Number 10 cat, he would meet fellow special advisers in the Cabinet Room.

"It never wears off," says James. "That feeling when you think how many amazing decisions have been made in this room.

"But you're always so busy that you have to focus on the day-to-day."

10 Downing Street is, of course, a house - meaning individual offices are in fact various rooms.

"My desk was in the old kitchen," says James.

"It sounds like I was relegated to the basement but it was actually a very nice room."

James' working day would finish at about 7pm or 8pm - unless he had a focus group to do.

He would often find himself jumping on a train to somewhere like Bridgend or Halifax.

"I would be in this front room in Grimsby talking to voters," James recalls.

"They had no idea I would be relaying their thoughts to the Prime Minister."

These sessions would often go on until 10pm, when James would catch a train back to London, ready to be back at Downing Street at 8am sharp.

By May 2019, following failures to pass a deal to leave the EU, the pressure was growing on Mrs May once again.

This was compounded by the Brexit Party storming to victory in the European Elections and the Conservatives finishing an embarrassing fifth.

"It was a slightly surreal situation," says James.

"By that time I realised I didn't want to try and stay on and wanted to go and do other stuff."

Mrs May eventually quit as party leader on May 24.

After leaving Number 10, James ran the strategy for Rory Stewart's Tory leadership campaign.

He has also made several media appearances - his favourite being a clash with Steve Coogan on Channel 4 News in the run-up to the December 2019 General Election.

The comedian said: "Alan Partridge is ill-informed and ignorant, and therefore he's a Conservative and a Brexiteer."

But James hit back: "This is exactly the attitude that means that these long-term Labour voters, who are good people, are leaving the Labour Party and going to the Conservatives."

And the pollster's prediction was proved right as the Tories won several "red wall" Labour seats. But a return to Downing Street was not on the cards for James.

"I wasn't approached by Boris' team and I didn't approach them," he says.

Now, aged 28, he has his own private polling company - J. L. Partners - with former Conservative Campaign Headquarters chief pollster Tom Lubbock.

But does James harbour ambitions of becoming an MP himself?

"Never say never. But I'd like to enjoy my 20s a bit more."

Having walked the corridors of power at such a young age, does the former adviser to the Prime Minister have any advice for others interested in a career in politics?

"The key is if you're enthusiastic about something and care about it and willing to put the work in - that's the number one thing people are looking for," James says.

"That's going to count a hell of a lot more than background or grades.

"And don't be afraid to follow your interests. It would have been so easy to stay at Deloitte, where the money was better, or to stay doing English at uni because I didn't want to cause a fuss.

"But if you really want something and you know deep down that's what you'll enjoy, just take the leap and enjoy it and it will pay off eventually.

"Practically, it's good to have experience, so write and send emails to every MP. Never stop badgering people.

"Get involved in local things. People in politics are always looking for help.

"It's initiative, initiative, initiative."

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