's supporters in believe she may have a secret weapon in her arsenal to beat next week: A 10-degree bump in temperatures.

Strategists think the improved forecast for Tuesday's primary will lift participation to record levels, and bring out the less-engaged voters she needs to beat frontrunner Trump.

'It's supposed to be in the mid 40s,' said Greg Moore, senior adviser to Americans for Prosperity Action (AFPA), an independent group backing Haley 'which in late January is what we call shorts weather.'

Haley finished in third place in Monday's caucuses, the first real test of the candidates running for the Republican nomination.

to make its decision, and a win for Trump could prove too much for Haley or Gov. Ron to overcome in the rest of the race.

New Hampshire was hit by a blizzard on Tuesday, but the temperature is forecast to tick up by about 10 degrees next week which could trigger a record turnout in the state's primary

But the north-east state's suburban and less religious population may offer Haley her best chance to halt Trump's juggernaut.

Moore said AFPA polling from last weekend showed Haley within striking distance of the former president.

'This is a race within a handful of points,' he said. 'Now some things might have changed between Sunday when we got our last numbers and now but this is within a handful of points. 

'You can count on your one hand.'

Monday's caucuses in Iowa took place in sub-zero temperatures. Two snow storms closed roads in the final week of campaigning. 

And Moore said it was a big factor in suppressing turnout. Some 110,000 Republicans made their way to church halls, school gymnasiums and convention centers — the lowest number in a decade.

The weather is warmer in New Hampshire and is like to get at least into the high 30s by Tuesday, ten degrees warmer than this week.

Haley's backers are banking on record numbers on Tuesday and expect the numbers to far surpass the 2016 Republican primary when 285,000 took part. 

This time around there is no meaningful Democratic primary, so they expect independents to take part in the Republican contest. 

Republican Presidential candidate Nikki Haley visits Kay's Cafe and Bakery in Hampton, New Hampshire on Friday as part of her last push to win the state

Donald Trump remains the clear frontrunner and Haley needs a strong result in New Hampshire to keep her momentum ahead of a tough test in South Carolina

'The other thing is, when you're getting that broad level of participation, you're pulling in more and more and more casual voters, more casual observers of politics,' said Moore. 

The group's canvassers are making calls and knocking doors to try to reach those people in the final days and make sure they vote for Haley. 

'We think that gives us a fantastic opportunity to have those conversations on the door to talk to people about about why they should vote for Nikki Haley,' he said.

'And we think that in particular, a lot of those people who are less and less and less politically engaged ... we find that we're having good conversations on the door.' 

The stakes could not be higher for Haley, the former governor of South Carolina.

Trump supporters drove through a blizzard Tuesday to see him appear in Atkinson

But the weather won't be as bad as Iowa, where temperatures were below zero

Trump romped to victory in Iowa with more than 51 percent of the votes on Monday

'She either has to win or have a very, very strong close second,' said New York donor Eric Levine, who is backing her.

The result of the primary will dictate what comes next.  

'New Hampshire is in large part about her,' he said. She has to be able to show that she can take Trump on, and I think New Hampshire is that state. 

'I think the polls are showing she's gonna do very well.'

DeSantis is running in distant third place.

His hardline war on woke plays less well with New Hampshire Republicans and he is spending the weekend campaigning in South Carolina.