Image source, Getty Images

Thanks for tuning in to our live coverage of the first primary election in the 2020 presidential contest.

Here are the key takeaways:

• Bernie Sanders won the night - barely - with a few thousand votes more than Pete Buttigieg

• Amy Klobuchar also saw success in New Hampshire, surging to take third place
• Elizabeth Warren and Joe Biden meanwhile had a dismal showing, with single-digit vote percentages
• The primary results have seen the 2020 field narrow with Andrew Yang and Michael Bennet dropping out in wake of their poor polling figures - nine candidates are left
• Exit polls found nearly half of all voters decided on their candidate only a few days before the polls, and noted that the debates had an impact on these decisions

So what happens next? Nevada has its caucuses on 22 February, followed by South Carolina's primaries on 29 February.

Want more? Not time for bed yet? You can follow updates to the story here and find out who had a good night (and who didn't) here.

Image source, Reuters/AFP

Bernie Sanders and Pete Buttigieg, the two current frontrunners, have an age difference of four decades - Sanders is more than double his rival's age.

In his speech in the past hour, Buttigieg mentioned admiring Sanders while he was in high school.

Buttigieg was born in 1982. At that time, Sanders was the mayor of Burlington, Vermont - a post he'd hold from 1981 to 1989.

When Buttigieg was graduating high school at age 18 in 2000, Sanders was a member of the US House of Representatives.

That same year, Buttigieg won an award for writing an essay about Bernie Sanders, external where he called him an "outstanding and inspiring example" of integrity.

"In a climate where even liberalism is considered radical, and Socialism is immediately and perhaps willfully confused with Communism, a politician dares to call himself a socialist? He does indeed."

Buttigieg became South Bend, Indiana, mayor in 2012 - at which point Sanders was in his second term as senator.

They're the first states in America to host a caucus and primary election in the long road to the presidency.

The states have a decent record for picking the eventual Democratic nominee. So far, they've opted for Pete Buttigieg and Bernie Sanders.

Those states' records are a bit more spotty when it comes to picking Republicans. Five out of seven final candidates have won New Hampshire since 1976 and in Iowa, just two since 1980.

Image source, Getty Images

Clinching victory in New Hampshire by just 2%, Bernie Sanders has currently gained eight delegates from the Granite State, and Pete Buttigieg has seven.

So after one caucus and (most of) one primary, where are we sitting with delegate totals?

• Pete Buttigieg: 14
• Bernie Sanders: 12
• Elizabeth Warren: 8

• Joe Biden: 6
• Amy Klobuchar: 1

(This number will change once the final result from New Hampshire comes in)

While New Hampshire and Iowa are important for momentum, it's worth remembering they make a small dent in the total delegate count: 1,991 delegates are required for a candidate to become the Democratic White House nominee. That's a loooong way away.

Image source, Getty Images

Who? He's the 2016 runner-up, who's starting to look like a serious contender to take on Trump in 2020

Key issues: Medicare-for-All universal healthcare coverage; raising taxes on the wealthiest Americans; upping the minimum wage.

One policy: Completely eliminating $1.6tn in existing student debt - regardless of income, unlike his rival Elizabeth Warren - and making public colleges, universities and trade schools tuition-free by taxing Wall Street.

You can read more about the candidates, their key issues, and analysis from the BBC’s Anthony Zurcher, here.

Jon Sopel
BBC News, New Hampshire

Image source, Getty Images

It's a win for Bernie Sanders, but it isn't a runaway victory.

Iowa and New Hampshire don't matter for the numbers, they matter for the symbolism: first in the nation caucus, first in the nation primary.

Bernie Sanders has got some momentum but I don't think this is quite as impressive a victory as he won four years ago.

Anthony Zurcher
BBC News, New Hampshire

Four years ago, Bernie Sanders took the New Hampshire primary with 60% of the vote. He won’t come close to that mark this time, but given the depth of the field the achievement is equally impressive.

What’s more, the order of the finishers helps Sanders as well.

Biden – the only candidate he trails in national polling - is wounded, perhaps mortally so. Pete Buttigieg finished a strong second, but his success outside the first two states is still an open question.

Warren, his closest rival for the liberal left vote, has yet to prove she can finish near Sanders. Amy Klobuchar’s success ensures she’ll stick around and the moderate support will remain splintered.

Four years ago, Sanders hit an electoral brick wall after New Hampshire. With plenty of money, a battle-tested national campaign organisation and divided opposition, his path ahead - while far from certain - looks the brightest of any in the field.

Read more from Anthony here

"We're going to unite together and defeat the most dangerous president in the modern history of his country," Sanders said, echoing his rivals' speeches in calling for togetherness in 2020.

"The reason we are going to win is that we are putting together and unprecedented, multigenerational, multiracial political movement."

He adds that he is taking on billionaires and candidates funded by billionaires, honing in on the key issues of healthcare and the economy.

Image source, Getty Images

Bernie Sanders is all smiles as he thanks the crowd of supporters cheering his name for their "great victory tonight".

"The reason we won tonight in New Hampshire, that we won last week in Iowa, is because of the hard work of so many volunteers," Sanders said. (This is a bit of a controversial statement as Sanders trailed Pete Buttigieg in Iowa by 0.1%.)

"This victory here is the beginning of the end for Donald Trump."

Bernie Sanders is projected to win the New Hampshire primary, the BBC's US partner CBS reports. He is about to appear in front of his supporters.

Image source, Getty Images

"So many of you decided that a middle class mayor and a veteran from the industrial west" was ready to take on the president, Buttigieg says to supporters in New Hampshire.

"And we will welcome new allies to our movement at every step."

With 83% of precincts reporting, Buttigieg sits in second with 24% of the vote - just 4,500 votes behind Bernie Sanders.

"We go forward to know that this is our chance, this is our only chance," he says

"And the stakes could not be higher, we cannot afford to miss the mark or miss the moment. We must get this right."

As Pete Buttigieg speaks, the crowd at the Bernie Sanders headquarters had a less than favourable response.

Sanders supporters chanted "Wall Street Pete" and booed the screen when Buttigieg appeared, according to our team on the ground in New Hampshire.

Speaking to supporters in New Hampshire, Pete Buttigieg begins by commending Senator Bernie Sanders, who is currently in first place.

"I respect him greatly to this day and I congratulate him on his strong showing tonight," Buttigeg says, before noting candidates Amy Klobuchar, Elizabeth Warren and Joe Biden, who trail further behind.

"Vote blue no matter who."

President Donald Trump has commented on the Democratic race via Twitter, noting: "A lot of Democratic dropouts tonight, very low political IQ".

Here's what he's said about the candidates:

• Elizabeth Warren - "Elizabeth Warren, sometimes referred to as Pocahontas, is having a really bad night. I think she is sending signals that she wants out."
• Pete Buttigieg - "Bootedgeedge is doing pretty well tonight. Giving Crazy Bernie a run for his money. Very interesting!"
• Michael Bloomberg (who was not on the ballot) - "A very bad night for Mini Mike!"
• Tom Steyer - "Impeachment King Steyer (how did that work out?) spent 200 million dollars and got less than 1% of the vote in Iowa and only 3% of the vote in New Hampshire. Could it be that something is just plain missing? Not easy to do what I did, is it?"

Nick Bryant
BBC New York Correspondent

It's clear that Bernie Sanders is the standard bearer of the Democratic left.

What we've got in the middle is muddled.

Moderate Pete Buttigieg has to share the stage with Amy Klobuchar - who had a very strong debate performance last week. Who will take the lead remains to be seen.

Pete Buttigieg keeps on eating into Bernie Sanders' lead. It's now down to about 3,800 votes, with about 75% of votes counted. Could he overtake Sanders?

Image source, Getty Images

The former Massachusetts governor says he is reflecting on his dismal New Hampshire polling. He's garnered less than 1,000 votes.

Patrick says he and his wife will "reflect on this outcome and make some decisions tomorrow morning about what the future of this campaign can and should be".

He is the only African-American candidate still in the running and one of two non-white contenders left in what began as a historically diverse Democratic field.

Two candidates - Andrew Yang and Michael Bennet - dropped out on Tuesday.

As the race in New Hampshire approaches its close with Bernie Sanders in the lead, we're wondering what conversations are happening between Quincy and her father Ron - a New Hampshire family divided over the Democratic hopefuls.

She's all for Sanders, but he's a Warren supporter. Given Warren's heavy loss in the state, Quincy may have bragging rights at the end of the night.

Watch their story below.

Jon Sopel
BBC News, New Hampshire

Bernie Sanders has run the most consistently focused campaign, he stays on message and has maintained an energy mostly unmatched by the other candidates.

He's got these core beliefs that people seem to like, particularly the young voters who turned out in large numbers to support him.

In contrast, I think Joe Biden's campaign is running on fumes. Heading to South Carolina tonight shows just how badly he has been doing.

Articulating a clear message for why he wants to win in 2020 has been much more problematic than it has been for Sanders.

About two-thirds of the New Hampshire votes are in - so where are we?

Bernie Sanders is holding on to his lead with 26% of the vote, followed closely by Pete Buttigieg, who has 24%. This is a difference of about 5,000 votes - the gap has narrowed quite a bit over the past half-hour.

Just behind them sits Amy Klobuchar, at 20%.

The three leaders are trailed by Elizabeth Warren (9%), Joe Biden (8%) and Tom Steyer (4%).

Only the top three are on track to claim any delegates.