Contenders for the Republican presidential nomination will face off in the second contest of their nominating process on Tuesday in New Hampshire, while Democrats compete there on the same day in a battle expected to be significantly less competitive.
The New Hampshire primary comes eight days after Iowa's Republican caucuses, which former US president Donald Trump dominated. His competitors will be eager to prove their candidacies are still viable despite Mr Trump's nearly 30-percentage point victory in the Republicans' first nominating state.
Here are some key facts about the primary:
When is it and how does it work?
The New Hampshire primary will take place on Tuesday with the precise hours dependent on the voting location. Unlike in Iowa and some other states, which rely on a relatively complicated "caucus" system, voters in New Hampshire cast their ballots much as they would during any other vote.
On the Republican side, 22 delegates to the Republican National Convention are up for grabs and will be awarded on a proportional basis. While that is a tiny portion of the 1,215 delegates needed to clinch the nomination, the state has traditionally played an outsized role in the nominating process because of its early spot on the calendar.
For Democrats, 33 delegates will be sent to the Democratic National Convention from New Hampshire, but their vote won't be bound by the primary results after a dispute over the timing of the vote. That means the New Hampshire primary will serve purely as a barometer of support for the Democrats in the race.
The national Democratic Party moved its first 2024 contest to South Carolina, which is significantly more diverse than New Hampshire's nearly 90 per cent white population, to better reflect the party. But New Hampshire state law requires it to host the first primary, and the Republican-controlled state government declined to make any legislative change to its primary date.
Who will be on the ballot?
Mr Trump, former UN ambassador Nikki Haley and Florida governor Ron DeSantis are all on the ballot in New Hampshire. Mr DeSantis and Ms Haley placed second and third in Iowa, respectively.
Mr DeSantis, facing exceptionally tough odds in New Hampshire, has opted to spend much of the the lead-up to the state's primary in South Carolina, where the next major Republican nominating contest takes place on February 24th. Ms Haley is a former South Carolina governor.
The main Democratic candidates on the ballot are US representative Dean Phillips of Minnesota and self-help guru Marianne Williamson. Democratic president Joe Biden is running for re-election but will not be on the ballot because of the primary date dispute. Some of his supporters, however, have launched a write-in campaign on Mr Biden's behalf.
Who is winning in the polls?
According to polling and analysis website 538, Mr Trump leads the Republican field in New Hampshire with 47 per cent of likely primary voters planning to cast a ballot for the former president. Ms Haley is in second with nearly 34 per cent support, and Mr DeSantis trails in third place with about 5 per cent support.
The Northeastern state is well-known for its relatively moderate, libertarian-minded brand of Republicanism. Moreover, the primary in New Hampshire is "semi-open," meaning voters who are not registered with any party can participate, which can help candidates perceived to be centrists.
Mr Biden is winning handily among Democrats, though the polling has been extremely inconsistent, with support for Mr Phillips, his closest competitor, landing anywhere between the mid-single-digits and the upper 20s depending on the pollster. The fact that Biden supporters will need to write his name on the ballot adds another element of uncertainty.
Why is the New Hampshire primary important?
On the Republican side, most political analysts agree that New Hampshire presents Mr Trump's competitors with their best opportunity to notch a victory - or at least a close second. This is particularly true of Ms Haley, who has gained significant momentum in the state in recent months.
If Ms Haley fails to mount a spirited challenge to Mr Trump, the former president could emerge as the presumptive Republican nominee to take on Mr Biden in the November general election. If Ms Haley does well, she will likely retain enough donors and interested voters to present a credible challenge in the subsequent weeks.
Even if Mr Trump loses, his competitors face an uphill battle. The former president leads by roughly 30 percentage points in South Carolina. Nationally, Mr Trump holds a 37-point lead, according to the most recent Reuters/Ipsos poll.
New Hampshire represents an opportunity for Mr Biden's Democratic challengers to prove there is appetite among voters to replace the party's incumbent. Mr Biden has dedicated most of his energy to South Carolina, which is home to his party's first fully sanctioned contest and where support from the state's Democrats helped him secure the 2020 nomination.
