After months of touring the country talking to voters and posing for photos with babies, United States presidential candidates are now facing their biggest contest: Super Tuesday.

For the five remaining Democrats vying to challenge Donald Trump, it’s a make-or-break event.

And now that Pete Buttigieg and Amy Klobuchar have dropped out of the race and endorsed Joe Biden, the field has narrowed from more than 20 candidates down to five.

Mr Biden, Michael Bloomberg, Bernie Sanders, Elizabeth Warren and underdog Tulsi Gabbard remain in the race to take on Mr Trump in November’s election.

So far, Ms Gabbard has not secured a single pledged delegate in any of the first four Democratic primary races, nor has she polled enough to appear on stage for a debate.

She hasn’t pulled out just yet.

From sunrise to sunset, registered voters across 14 states and one territory will fill community hubs and school halls to vote in primaries or caucuses for their favourite candidate.

It’s called Super Tuesday because it’s the day when the most delegates can be snapped up by candidates.

A delegate is a person who represents their state at national party conventions.

Candidates need at least 1991 pledged delegates to win the Democratic nomination in the first round of voting at the party’s nominating convention in June.

About one-third of all pledged delegates will be decided on Tuesday alone.

Early indications were the candidate with the best chance of doing that is Senator Sanders, who is leading in the polls.

But if the election of Mr Trump in 2016 has taught us anything about American politics, it’s that anything is possible.

Who are the remaining frontrunners?