Nikki Haley has finally worked out how to deal with Donald Trump.

The former South Carolina governor, who served in Mr Trump’s administration as his UN ambassador, has always been uneasy about criticising her former boss.

But like all of Mr Trump’s challengers she must strike a delicate balance between poaching supporters from his enormous polling lead and disastrously upsetting the “Make America Great Again” wing of the party.

As the clock ticks down to the Iowa caucus on Monday – the first round of state-by-state voting to decide the Republican presidential nominee – Ms Haley has a new message about the former president: he might have good ideas, but he is more trouble than he’s worth.

“I think president Trump was the right president at the right time to break the things that we needed,” she told a packed room of voters in Ankeny, near Des Moines, on Thursday.

“I agreed with a lot of his policies. But rightly or wrongly, chaos follows him.”

“We can’t be a country in disarray and have a world on fire, and go to four more years of chaos because we won’t survive it.”

The message is designed to smooth over the differences between Ms Haley’s establishment wing of the GOP and Mr Trump’s anarchic supporters. Voters on both sides appear to be persuaded by it.

And it appears to be landing, to an extent. Polls last night showed Ms Haley leapfrogging her rivals to take second place in Iowa.

Candidates are criss-crossing a rural state the size of England, cars skidding on ice and snow with temperatures lower than -20C, to meet voters wherever they can find warmth.

“I have people in my family who are on opposite ends of the political spectrum, and I feel like she’s somebody who can start to bring us back together,” said Anne Darby, on the first floor of a nondescript office block for Ms Haley’s latest campaign stop.

The retired teacher and former Trump supporter who runs a children’s riding school, added: “I agree with a lot of what Trump did, but I feel like he’s an alienator. I don’t want him back in office. I don’t like him. I want somebody who can talk to both sides.”

Tom Agnigsch, a retired IT director, agrees. “I supported Trump last time, but never again,” he said.

“Chaos follows. We need somebody with higher moral conviction, better character. Somebody that we can respect and look up to as well as the rest of the world.”

Anne and Tom will likely meet again on Monday to debate and vote behind closed doors, district by district – an odd quirk of the US primary election season.

Hedging her bets

Unlike Ron DeSantis, who has thrown almost all of his campaign’s resources into the Iowa caucus, Ms Haley is playing a longer game.

Her campaign team expected to perform poorly in Iowa – a socially conservative, rural state where Mr Trump and Mr DeSantis poll well – and have focussed on building a ground campaign in the next two primaries, New Hampshire and South Carolina.

In New Hampshire she is now in with a serious chance of overtaking Mr Trump, after the withdrawal of Chris Christie, her main rival on the moderate wing of the race.

Prior to his decision to suspend his campaign, Mr Christie had 12 per cent support in the Granite State – enough to give Ms Haley the edge on Mr Trump if all of his supporters switch to her.

Her supporters hope that Mr Christie’s unfortunate hot mic moment on Tuesday, in which he revealed he thought she would be “smoked” by Mr Trump in the primary, does not prove accurate.

South Carolina, her home state, votes at the end of February, when Ms Haley’s team hope she will have built enough momentum to switch from underdog to frontrunner.

What her team never expected was that she would overtake Mr DeSantis in Iowa, where the Florida governor has spent weeks tirelessly travelling through almost every town in the state.

A new poll released on Friday showed she is now in second place, with the support of 20 per cent of GOP voters to Mr Trump’s 54 per cent.

The survey is a major boost for her campaign, and those close to her hope that beating Mr DeSantis in Iowa could knock him out altogether, leaving her as the sole challenger.

Trump ‘sees Haley as a threat’

“I think Monday is the end of the DeSantis campaign, and then it’s just Haley versus Trump,” said Eric Levine, a Haley campaign fundraiser in New York.

“I think this potentially becomes a long drawn out slugfest between Trump and Nikki Haley. And I think at the end of the day, I remain hopeful that she can pull it off.

“All of a sudden now, Trump is focussed on her. He was attacking DeSantis, he was attacking Biden.

“Now he’s just focussed exclusively on her. He obviously sees her as a threat. He wouldn’t be wasting his breath on her if he didn’t think she was a threat to him.”

Challenges remain

For all the good news in the polls for Ms Haley, there are some who remain sceptical about her ability to overtake Mr Trump on a national scale.

There are major policy differences between the pair on key issues, like the war in Ukraine.

Mr Trump has said he would end US support for Kyiv, and end the war in “one day”, while Ms Haley, whose husband was deployed in Afghanistan, has been a vocal supporter of more muscular American involvement in global affairs.

“The last thing I want any military man or woman to have to do is have to go fight a war,” she told voters on Thursday. “But you have to understand your enemies before you know how you can defeat them.”

On abortion, one of the trickiest issues for Republicans, Ms Haley has dodged difficult questions about nationwide bans and says she would leave the decisions to individual states. Mr Trump has hinted he would look at federal action, if broad support could be found.

Ms Haley prefers not to discuss these policy differences, instead pointing to polls showing that of the two candidates, she would beat Joe Biden by a much larger margin – paving the way for a four-year Republican domination of political institutions.

“That’s bigger than the presidency,” she said. “You go into DC with a double digit win – that’s a mandate, to stop the wasteful spending, get our economy back on track…to get our kids reading again and go back to the basics on education.”

Reaching the crescendo of her stump speech, she finishes: “No more excuses. A mandate to bring life back to our country and a mandate for a strong America we can be proud of. Don’t you want that again?”

With just three days to go until voters hit the polls, it increasingly feels like they do.