Donald Trump's commanding victory in Iowa underscores his enduring appeal to a wide swathe of Republican voters, and his campaign's sophisticated, data-driven ground game. But the next nominating contest in New Hampshire will test whether he can replicate that success in a less conservative state.
While Mr Trump remains the prohibitive favourite to secure the Republican Party's presidential nomination, he needs a convincing win in New Hampshire to ensure his surviving rivals have little to no path left to outmanoeuvre him. He can then turn his attention to his Democratic opponent in the November 5th election, US president Joe Biden, earlier than usual in the primary calendar.
Mr Trump's win on Monday night in Iowa was broad-based, with the former president taking all but one of the state's 99 counties, including in the suburbs outside Des Moines.
Independents
Now he heads to New Hampshire where he will face a more diverse electorate, with fewer evangelical Christians and a larger proportion of independents. Mr Trump is still the frontrunner in the Northeastern state's January 23rd primary, but former UN ambassador Nikki Haley, who appeals to more moderate voters, has closed the gap in recent opinion polls.
Critically, unaffiliated voters outnumber Republicans and Democrats in New Hampshire and can vote in the primary.
"Trump is strongest in an intensely partisan Republican environment. To the extent that you dilute that, it creates issues for him," said Tom Rath, a veteran Republican strategist in New Hampshire.
Ms Haley, 51, has been blanketing New Hampshire with TV ads with one suggesting both Mr Trump, 77, and Mr Biden, 81, are past their primes and fixated on the old grievances. She has also been endorsed by New Hampshire’s governor, Chris Sununu, who will join her at events over the next week.
Ms Haley came a distant third in Monday's contest as Mr Trump won almost every demographic group, but she did get some good news that could presage a better result in New Hampshire: polls showed she swept up most of the moderates, although they only made up a sliver of those who voted.
'Quiet resolve'
Rick Jarvis, 72, who installs HVAC units, was typical of the three dozen Trump supporters interviewed by Reuters in Iowa over the past two weeks. Mr Jarvis said he supports Mr Trump because he believes he will reduce inflation and restrict immigration.
"I still think Donald Trump is the best answer to put this country back to where it needs to be again," Mr Jarvis said.
When Mr Trump kicks off his final New Hampshire push with a rally in Atkinson on Tuesday night, the ground operation that turned out voters like Mr Jarvis will in many respects look similar to Iowa: volunteers collecting data on attendees which will be put into a database, allowing for follow-up calls and texts.
But unlike in Iowa, where more than 2,000 Trump caucus captains organised their precincts and sought to persuade voters with speeches at gatherings at churches, high schools and community centres on Monday night, in New Hampshire voters will cast their ballots individually throughout the day next week.
Enticed with white-and-gold limited-edition hats and VIP treatment at rallies and other campaign events, the Iowa caucus captains were a linchpin of Mr Trump's get-out-the vote effort in the Hawkeye State. Many were pastors, making them natural leaders in their communities who could also help the campaign target the evangelical voting bloc that is so critical in Iowa but barely registers in New Hampshire, the Granite State.
Joel Tenney, an evangelist who was a caucus captain in the small town of Tiffin, estimated he made more than 1,000 calls in his region of Johnson County, Iowa, working off a list of voters provided by the campaign.
"Our job is to call people to get them to go to caucus. Then when they get to caucus our job is to convince them to vote for Trump. That's exactly what I did," Mr Tenney said, showing Reuters a text exchange in which he successfully chided a sick couple to show up on Monday night. "One couple I dragged out of bed."
In New Hampshire, Mr Trump's campaign will not be able to rely on activists like Mr Tenney rallying and seeking to persuade voters through to their decision at a caucus site.
"There's not a lot of vocal out in-your-face support for Trump," said Gregg Hough, chair of the Republican Party in New Hampshire's Belknap County.
But Mr Trump has a solid ground game with strong local leaders in his state, Mr Hough said. He described the mood among Trump supporters as one of "quiet resolve".
Opportunity for Haley
According to polling website 538, Mr Trump leads in New Hampshire with 43 per cent of likely primary voters planning to cast a ballot for him. Ms Haley is in second with 30 per cent support, and Florida governor Ron DeSantis trails in third place with about 6 per cent support.
In Iowa, Mr Trump beat the 45-year-old Mr DeSantis, who came in second, by 30 percentage points.
New Hampshire's mix of moderate Republicans and independent voters arguably gives Ms Haley her best shot at slowing Mr Trump's momentum. If she can come in a close second to Mr Trump, or even beat him there, it could dent the narrative that his winning the party's nomination is inevitable.
There are more than 340,000 independent voters in New Hampshire, more than the number of registered Republicans or Democrats.
In a two-way race with Ms Haley, Mr Trump’s pollster showed Mr Trump winning 52 per cent to 44 per cent. Mr DeSantis' presence, however, may muddy that dynamic.
"She doesn't need to win in New Hampshire, but she does have to finish strongly so the narrative coming out of New Hampshire is that it is a two-person race," said Jim Merrill, a veteran Republican strategist in the state.
