Huddled around a desk at Turning Point HQ in Phoenix, Arizona, JD Vance persuaded Charlie Kirk and Tyler Bowyer to back his campaign for Senate.

The year was 2021 and the future vice-president, best known at the time as the author of Hillbilly Elegy, his memoir about America’s forgotten working class, was making his first foray into politics.

“People were like, ‘what are you doing? You guys are stupid; this is crazy,” recalled Mr Bowyer, Kirk’s former right hand man and the chief operating officer of Turning Point Action.

Four years later, the conservative behemoth widely credited with inspiring a generation of younger voters to support Donald Trump in 2024 is championing Mr Vance to run for the White House in 2028. “JD Vance must be president,” Mr Bowyer told The Telegraph. “There’s nothing else. This is the mission.”

Both then and in the 2026 midterm elections, Arizona is set to play a crucial role in determining the fate of the Republican Party.

“This is the epicentre for what is statistically one of the most important states for Republicans to win,” said Mr Bowyer, speaking at the group’s head office in early December.

The room is strewn with memorabilia honouring his recently murdered friend, and behind him sits a colour-coded map of the US highlighting the 10 key target states his organisation is focusing on in the midterms.

“If we’re successful, Arizona is going to become the model for how the Right can take a state that is swinging towards the Left... and then flip it back so that conservatives can win,” he said.

The Grand Canyon State has been a pivotal arena for Republican politics throughout the Maga era.

It was one of the first states where Mr Trump rallied in December 2015 as he sought to build national support, and where he focused his efforts to overturn the result of the 2020 election.

Phoenix, the state capital, is the home of Turning Point, the grassroots organisation that has grown into a dominant force in Republican politics. Two hours’ drive away, the suburbs north of Tucson are where Steven Bannon, Mr Trump’s former chief strategist, spends his time when he is not in Washington, DC.

It is also a state of contrasts, serving as a window into the issues dividing America.

The sun-scorched desert hinges between old frontier ranchers and the young, multicultural Phoenix metropolis that is rapidly replacing them. A place where suspicion of Washington and libertarian instincts collide with reliance on federal border enforcement, and where politicians who pride themselves on their maverick independence have been subsumed by hyper-partisan national politics.

Having long been a red jewel in the GOP’s sunbelt crown, voting Republican in all but one presidential election between 1952 and 1996, it has turned more purple over the past decade.

Its first and sixth congressional districts voted Republican in the last two election cycles by a margin of less than four per cent, making them two of the most competitive seats in the country.

With fewer than 20 seats earmarked as toss-ups in next year’s midterm elections, both districts are set to be key battlegrounds in deciding whether Democrats can flip the Republicans’ 220-213 majority in the House of Representatives.

“We have two of the most competitive congressional seats in America. So what happens here in 2026 is going to be critical, not just for Arizona, but for the country,” said Karrin Robson, a Republican running for governor.

In 2024, it was the swing state with the highest proportion of Hispanic voters (32 per cent), who, persuaded by Mr Trump’s strong message on the economy, voted Republican in historic numbers.

But a year into his presidency, inflation remains stubbornly high at 2.7 per cent, two thirds of voters say the economy is in poor shape and the president’s personal approval ratings have sunk to 31 per cent, the lowest of any point during his two terms, according to a recent Associated Press-NORC poll.

The affordability crisis and low consumer confidence have caused the president’s voter base to fracture, helping the Democrats to a string of local election victories including in New York, New Jersey and Virginia.

The impact on Latino voters, who now make up the largest minority voting bloc in the country, could have dire consequences for Republicans.

“It’s the cultural issues that animate non-hispanics and black voters,” said Mike Madrid, a Republican strategist and author of The Latino Century. “[Latinos] are much more concerned about paying rent than about who’s using which bathroom.”

Unless Latinos start to feel better about the state of the economy, he said, the results will show a “dramatic movement away from the Republicans”.

On a ramshackle industrial estate on the backstreets of Nogales, a border town south of Tucson, Francisco, 44, said he voted for Mr Trump in 2024 but now regrets it.

“When he was there [from 2016-2020] the economy was good. Now, I think it sucks,” he said.

The married father-of-four who runs an auto repair shop said he feels “betrayed” by the government in Washington, adding: “I don’t know if I will vote again to be honest.”

Economic frustrations in Arizona have curdled into fear as the White House has ramped up ICE raids against Hispanic communities as part of its push to arrest up to 3,000 migrants a day.

Videos have flooded social media showing Immigration and Customs Enforcement agents wrestling suspected illegal migrants to the ground to the delight of Mr Trump’s base.

The administration claims that it is targeting “gang members and murderers”, but the arrest of some women and children has left the Latino community shaken.

Luis Reyes, a 22-year-old government relations worker from Phoenix, worries that if his undocumented mother is detained, he will be the sole provider in his family, looking after his wheelchair-bound older brother and two younger siblings.

“I’d have to become the head of the household, support all my siblings financially and basically do everything. That creates a lot of fear for a lot of people,” he said.

Alexis Torres, 22, an industrial engineering student at Arizona State University, said that his uncles work on construction sites that have been raided by ICE.

“It’s truly scary and it opens up their eyes that every day could be their last,” he said.

Among border state residents, approval of Mr Trump’s handling of immigration has dropped from 42 per cent to 33 per cent since March, according to a survey by the Public Religion Research Institute (PRRI).

“The combination of Trump’s anaemic performance on the economy, combined with his immigration crackdown... have really taken a toll with respect to Trump support among Hispanic Americans,” said Dr Melissa Deckman, the CEO of PRRI.

According to Mr Madrid, although ICE raids are a “tertiary consideration” for Latino voters, “they are extremely mobilising and are no doubt a part of what is driving anger, fear and turnout”.

The perceived cruelty of the administration’s deportation policy – including a recent series of Christmas-themed social media posts showing Father Christmas as an ICE agent telling undocumented migrants to go “ho ho home” – has left a bad taste in the mouth of even some dyed-in-the-wool Maga voters.

Jeannie Gage, 51, is part of Leaving Maga, a growing movement of former Trump hardliners who have recanted their beliefs.

The mother-of-four grew up in Arizona’s Mormon church, was a life-long Republican and felt “enchanted” by Mr Trump when he first ran for president.

“When I first heard the words ‘let’s make America great again’, I stood in my living room and cried,” she said.

However, after leaving the Mormon church two years ago, she broke with the Maga movement during the 2024 campaign, having grown disenchanted with the administration’s policy towards immigrants.

“I saw for the first time just the cruelty of Donald Trump and some of the Maga people,” she said.

Describing her experience of Maga as being “trapped in a cult”, she said she now hears from thousands of people every month who have also left behind Mr Trump.

Despite pushback, Republican candidates and strategists in Arizona remain optimistic that voters broadly remain on board with the president’s immigration agenda.

“There is now more than ever, a greater understanding, even within the Hispanic community, of the impact of illegal immigration, and how it’s affecting their American dream,” said Shelby Busch, the vice-chairman of the Maricopa County Republican committee.

Speaking at the party’s central office on the outskirts of Phoenix, Ms Busch said she believes most Latino voters in Arizona are happy with the administration for stemming uncontrolled immigration, which she said had driven up house prices and crime and blighted businesses.

“These are truly conservative, family oriented people, and I believe they’re going to turn out and vote in a way that’s going to best suit their family and communities,” she said.

One such person is Jose Castro, the Hispanic American vice-chairman of the Santa Cruz Republican Party, who said concerns about illegal migration played a “big part” in his decision to leave behind the Democrats.

Proudly wearing a red Maga hat, one of several in his collection, the 27-year-old said he had been called a “race traitor” for switching allegiance.

“We were tired of being told you have to vote for [the Democrats] because of the colour of your skin,” he said. “A lot of us were like, ‘well you actually have to win our vote’.”

Yet whether his friends vote Republican again in 2026 depends heavily on the state of the economy, he said. “They have families and children; they want to see their living standards improve.”

While Ms Busch conceded “people aren’t seeing a significant decrease in costs” yet, she believes there is growing “enthusiasm” around the actions of the administration and that voters “finally see a light at the end of the tunnel”.

The challenge she foresees for Republicans going into the midterms and beyond is finding candidates who can “bridge the gap” between Mr Trump’s brand, which drew in hordes of younger and minority voters, and the key policy issues affecting voters.

“The Republican Party really needs to do a great job of messaging and really driving the people to the polls this year in a way that has never historically been done in the midterms,” she said.

Grasping the nettle, Arizona gubernatorial candidate Ms Robson is pitching herself as a business executive – rather than a politician – and has pledged to bring down housing costs in the state by cutting through red tape.

“The affordability crisis is real,” she said, laying the blame at the door of Katie Hobbs, the state’s current Democratic governor.

“We have a governor who doesn’t know anything about business or the economy,” she said. “Our cost of living in Arizona has skyrocketed.”

Learning from the success of Democrats in November’s local elections, party candidates in Arizona’s key swing districts are also hammering home a message focused on the cost of living.

In District 6, JoAnna Mendoza, a Hispanic American military veteran, is trying to thread the needle between Mr Trump’s immigration crackdown and the economic consequences.

While pledging to put drug traffickers “on notice”, she points out that cattle ranchers in her district rely on immigrant workers and trade with Mexico that has been “ruined” by tariffs.

“It is a mess, and people are sick and tired of the instability,” she said.

In District 1, another battleground seat, Democratic candidate Marlene Galan-Woods pointed to Republicans’ “atrocious” decision to allow Obamacare premium healthcare subsidies to expire as further evidence of the Trump administration ignoring the plight of ordinary Americans.

“The Democrats have the backs of the middle class, and as a Latina, I can certainly communicate to my Latino constituents in Spanish that I will make life more affordable,” she said.

A central challenge Republicans face is turning out voters without Mr Trump on the ballot – particularly in a midterm election where incumbent parties tend to suffer.

To do so, the party must rally around a common set of principles, in the same way the Democrats have recently turned the issue of affordability to their advantage.

Yet in recent months, infighting between different wings of the party over whether extremist voices should be allowed within the Maga coalition have spilt out into the open, after Tucker Carlson platformed Nick Fuentes, a holocaust denier, on his podcast.

Tensions came to a head in Phoenix in late December at AmericaFest, a conservative conference hosted by Turning Point, where differing visions for the future of the Republican Party in the post-Trump era vied for supremacy.

Pleading for calm, Erika Kirk said that since the assassination of her husband, who acted as a unifying force within the Maga movement until he was shot dead during a talk at Utah Valley University in September, “we’ve seen fractures, we’ve seen bridges being burned that shouldn’t be burnt”.

At Turning Point HQ, Kirk’s absence still hangs heavy in the air. Outside the gate, two shrines, dotted with wreaths and American flags, remain in place to honour the organisation’s fallen leader.

“It’s like losing a family member, business partner and one of your best friends all in one,” said Mr Bowyer, his voice cracking.

But with Kirk gone, the group has a strategy in place to fulfil their founder’s vision for Republican domination.

Pointing to his map of 10 key swing states, Mr Bowyer outlined Turning Point’s methodical plan to target low-propensity voters, combining a relentless ground game, where staff are working alongside thousands of ballot chasers in each of the states, with selecting candidates who voters recognise, including a television sheriff and a retired American football kicker.

“We’re throwing the kitchen sink at this thing,” he said. “No one has the same credibility or name ID that Donald Trump has, so it’s harder to have that conversation at the door.

“The challenge now is to educate people and to get those candidates well known.”

On a shelf behind Mr Bowyer, standing incongruously next to a photograph of Nigel Farage in a sombrero, is a signed edition of former Arizona senator Barry Goldwater’s The Conscience of a Conservative.

With its emphasis on small government and states’ rights, the 1960 book became a foundational text of the post-war Republican Party, credited with revolutionising conservatism from an elite intellectual project into a mass political identity.

Then as now, the conservative movement is in a state of flux. If it cannot unite behind a joint set of issues, a counter-revolution could be in the offing.