Image source, Getty Images

California has made its Super Tuesday debut. Lawmakers moved the state's primary up in an effort to increase impact, and polls close in a few minutes.

The state will certainly have a noticeable effect on the 2020 race - California is America's most populous state, its biggest economy and it will award 30% of the delegates available on Super Tuesday.

But who takes home the lion's share of those delegates could take a while to figure out.

California boasts more than 20 million registered voters and most people post their ballots. For any contentious contests, results won’t be called until every vote is counted, which could take anywhere from days to weeks.

No-one other than Joe Biden and Bernie Sanders has mounted a real fight on Super Tuesday. It is now very definitely a two-horse race to become the Democratic nominee.

Biden has had an extremely successful few hours and at this point is in the driving seat after doing well in southern states, winning over more moderate Democrats and doing well among black voters.

But Sanders is very much still in the running as we begin to hear from western states that lean more liberal, like the behemoth of California.

Biden is projected to win:

• Virginia
• North Carolina
• Alabama
• Tennessee
• Arkansas
• Oklahoma
• Minnesota

Sanders has won:

• Vermont
• Colorado
• Utah

No wins yet for Elizabeth Warren, though her home state, Massachusetts, has no definite winner yet.

Texas and Maine are also still too close to call.

But remember, candidates need 1,991 delegates to win the nomination. At this stage, Biden has 318 and Sanders 215. We're a long way off yet.

Exit polls suggest Joe Biden will win the midwestern state of Minnesota.

It's possible the support of the state's senator Amy Klobuchar, who dropped out of the 2020 race and endorsed Biden this week, helped swing the state in his favour.

Minnesota has 75 delegates in all, and it's likely Sanders will also get a share of those as he had been polling well in the state.

Bernie Sanders is projected to win the western state of Utah, as expected. He won the state in 2016 too.

The state has 29 delegates which will be divvied up among the candidates based on vote count.

But it's worth remembering that Utah has not voted for a Democrat in the presidential election since 1964, when it picked Lyndon B Johnson, so tonight's win may not translate to success in November.

"It's a good night," Biden repeats three times as he takes the stage in Los Angeles to speak to supporters. "And it seems to be getting even better."

"They don't call it Super Tuesday for nothing."

"Folks, it's still early. But things are looking awful, awful good," he adds.

He says the press were too quick to announce his demise only a few days ago.

"Well, it may be over for the other guy," he roars, in a veiled swipe at rival Bernie Sanders, who had been leading in the delegate count before tonight.

CBS News projects Biden will do best in Oklahoma - the sixth state he has won tonight. The state has a total of 37 delegates.

Polling last week had suggested Bloomberg or Sanders could do well.

Remember, it's still unclear how many delegates Biden will get - that's determined proportionally based on the number of votes.

Biden is on stage in Los Angeles right now - we'll bring you his comments as soon as we get them.

Still on stage in Vermont, Sanders outlines his policy proposals to more praise from the crowd in his home state.

"What makes this movement unique is we are taking on the corporate establishment, we are taking on the greed of Wall Street, the greed of the drug companies ... the greed of the insurance companies, and given the existential crisis of climate change, we are saying to the fossil fuel industry - their short term profits are not more important than the future of our country and the world."

"It is our campaign, our movement that is best positioned to beat Trump," he adds.

"You cannot beat Trump with the same-old-same-old kind of politics."

Arkansas, where 31 delegates are up for grabs, is projected to go in Biden's favour.

He never campaigned in the southern state and still won there.

Again, it's unclear for now what his share of the victory will be, and therefore how many delegates he will win.

Of note: Arkansas has opted for a Democrat in a presidential election only twice in 40 years, and even then, it was local boy Bill Clinton, both times. Might that change in 2020?

A smiling Bernie Sanders has taken the stage in Burlington, Vermont.

"Everybody said it couldn't be done," he says to cheers, "but tonight I tell you with absolute confidence: We're gonna win the Democratic nomination. And we are going to defeat the most dangerous president in the history of this nation."

He is briefly interrupted with chants of "Bernie, Bernie" from the crowd.

Mike Bloomberg will "re-assess" his candidacy, his campaign manager says, leading to speculation that he may drop out in the coming hours or days.

But his top aide cautioned that this reassessment "doesn't mean much yet".

Elizabeth Warren has yet to see a win tonight, but earlier in the evening, promised she would continue to fight.

Massachusetts, the state she represents in the US Senate, has yet to be decided, and Warren was speaking before those results came in.

"Cast a vote from your heart," she told voters.

Marianna Brady
BBC News

Over the course of the year, a group of young people will share their opinions with us at the BBC as the US moves to elect its next president.

Today, we’ve been introducing you to some of our Democratic panelists in Super Tuesday states.

Next up: first-time voter Charles Frederick, 17, from Utah. Polls in his home state are the next to close in a few minutes, at 20:00 local time (03:00 GMT).

What’s at stake in this election?

The restoration of a free and fair democracy in the United States. It is not extreme to say that, under Trump, every piece of law from basic civil liberties to the separation of power has been eroded and is barely holding together. If he wins a second term, he will not be beholden to any voters, and I do not know if the famed "American experiment" can survive that.

Do you know who you are voting for? If not, what will decide your vote?

I plan to vote in the primary for Elizabeth Warren, and in the general election for whoever the Democratic candidate is.

My vote in the general was decided on November 9, 2016 - Trump cannot be allowed a second term. I may disagree with some of the Democratic primary candidates on certain issues, or believe they are not the best person for the job, but any of them are infinitely better than the current president.

My vote in the primary, by contrast, was uncertain for much longer. I decided on Warren because I believe she is the candidate who both knows how to and will use the office of the presidency to make the United States a better place.

What should someone outside the US know about your state that makes it unique?

Utah is one of the most Republican states in the nation, but the reason Utah is so Republican in national elections - the heavily Mormon population - is also what makes our state and politicians unique among Republicans.

Simply put, Mormons don’t like Trump - in 2016, he received only 13% of the vote in the Republican primary here, and never broke 50% even in the presidential election. Thus, our politicians, while Republican, are freer to buck the president without fear of repercussion from his voters.

Our senator Mitt Romney became the first senator to vote to indict a president from his own party during the impeachment trial.

Bernie Sanders is on track to do best in Colorado, according to an exit poll by CBS News, the BBC's US partner.

He was expected to win, as out-of-state migration and population growth has seen Colorado become increasingly Democratic.

Colorado has 67 delegates, but it's unclear right now how many he will win.

Jane O'Brien
BBC News, Burlington, Vermont

Bernie supporters are feeling nervous tonight.

Only a handful of results are in but, so far, it hasn’t been great news for the 78-year-old Vermont senator who just last week held the position as this race’s definitive front runner.

The comeback kid - aka Joe Biden - is back with momentum and Sanders’ supporters are dealing with a new reality: the former vice-president is now a formidable opponent, and ready to put up a fight.

But here in Vermont, supporters are determined to make tonight a victory rally.

After all, this is Sanders’ home state - and he won here by double digits.

They say the night is young. There are still high hopes that he’ll do well in California, the state with the most delegates up for grabs.

Image source, Getty Images

The story of Super Tuesday so far? It's Biden v Sanders.

Biden's done well in southern states, winning over more moderate Democrats and doing well among black voters.

But Sanders is very much still in the running as we begin to hear from western states that lean more liberal, like the behemoth of California.

And a CBS News exit poll shows Sanders won 45% of the Latino vote in Texas, compared with 24% for Biden.

Biden is projected to win:

• Virginia
• North Carolina
• Alabama
• Tennessee

Sanders has won:

• Vermont
• Colorado

Michael Bloomberg won American Samoa - and Tulsi Gabbard is projected to win a delegate there too.

No wins yet for Elizabeth Warren, though her home state, Massachusetts, has no definite winner yet.

Texas, Oklahoma, Arkansas, Maine and Minnesota are also still too close to call.

But remember: candidates need 1,991 delegates to win the nomination. A total of 1,357 will be doled out after today's votes are counted. Winning a state does not mean winning the entire delegate pool, however - that's determined by vote percentage.

Our US partners CBS project Joe Biden will win yet another southern state, Tennessee, although it's unclear how many of its 64 delegates he will win.

Voting there was extended after 25 people were killed in a tornado late on Monday.

Jon Sopel
BBC North America Editor, Burlington, Vermont

In politics everything is about expectation - and managing it.

Coming into Super Tuesday there was an expectation that Sanders would become a runaway train and nobody would be able to catch up with him.

It hasn't been that way tonight. When Virginia was quickly declared for Biden, things started to suddenly look like a two-horse race.

With all that expectation for Sanders, all of us in the media are now saying 'Wow, Biden is doing much better than expected'.

It's been a pretty miserable night so far for Michael Bloomberg, apart from winning in American Samoa.

BBC Newsnight has searched far and wide for his campaign in California, but can't find any trace of his nearly half billion-dollar operation.

Watch as our team wandered around two Bloomberg offices, which are completely empty of any of his alleged 800 campaign staff who are meant to be working in the state for the billionaire candidate.

Here are the latest results, based on exit polls from the BBC's US partner CBS News:

• Texas (228 pledged delegates) - toss-up between Joe Biden and Bernie Sanders

• Minnesota (75 pledged delegates) - toss-up between Biden and Sanders

Tennessee is leaning towards Biden, but there's no firm projection yet, according to CBS.

Polls have also closed in Colorado but there hasn't been a projection yet.

In any case, the story of the night right now looks like the race between Joe Biden and Bernie Sanders.

Image source, Getty Images

Welcome to the big leagues. Texas is America's second-biggest economy and second-biggest state by size, population, and delegate count.

How many delegates? 228

Who will do best? It had been very close between Sanders and Biden here. Maybe Biden's momentum has carried through to here as well.

Who could do well? Elizabeth Warren has been third or fourth in most polls.

One piece of context: There's reason to think that the so-called sleeping giant of the Texas Hispanic vote is about to wake up. In the 2018 midterms, 46.9% of registered Hispanic voters turned out, a leap from 24.4% in 2014.