Seven casino-resorts on the Las Vegas Strip are among the venues during the Nevada Democratic presidential caucuses on Saturday, the third contest in a 2020 primary season that has so far been marred by chaos and uncertainty.

The exercise of democracy inside gambling centres is just one element that distinguishes the first candidate contest on the western side of the US, which will, more importantly, test the candidates’ strength with black and brown voters for the first time in 2020 with the earlier fixtures in Iowa and New Hampshire having taken place in overwhelmingly white states.

“Nevada represents an opportunity for these candidates to demonstrate their appeal to a larger swathe of our country,” said state attorney general Aaron Ford, a Democrat who is not endorsing a candidate in the crowded field.

Nevada’s population, which aligns more with the US as a whole than the opening elections in Iowa and New Hampshire, is 29% Latino, 10% black and 9% Asian American and Pacific Islander.

The vote comes at a critical moment for the Democratic Party as self-described democratic socialist Bernie Sanders emerges as the clear front-runner and a half dozen more moderate candidates savage one another for the chance to emerge as the preferred alternative to Sanders.

The ultimate winner will represent Democrats on the ballot against President Donald Trump in November with the White House incumbent not facing a contest in Nevada for his party’s nomination.

Yet on the eve of the caucuses, questions lingered about Nevada Democrats’ ability to report election results quickly as new concerns surfaced about foreign interference in the 2020 contest.

Election 2020 Debate
Amy Klobuchar performed well in New Hampshire (Matt York/PA)

Campaigning in California, Mr Sanders confirmed reports that he had been briefed by US officials about a month ago that Russia was trying to help his campaign as part of Moscow’s efforts to interfere in the election.

“It was not clear what role they were going to play,” Mr Sanders said.

“We were told that Russia, maybe other countries, are going to get involved in this campaign.”

He added: “Here’s the message to Russia: Stay out of American elections.”

Despite the distraction, Mr Sanders enters Saturday increasingly confident, backed by strong support from Latinos and rank-and-file union workers who have warmed to his fiery calls to transform the nation’s economy and political system to help the working class.

In a fiery speech the night before the caucuses, Mr Sanders lumped the “Democratic establishment” in with the corporate and Republican establishment, saying they cannot stop him.

He said the establishment was “getting worried” about a multiracial coalition that wants higher wages and health care.

Mr Sanders also picked up the endorsement of Dick Van Dyke with the Chitty Chitty Bang Bang and Mary Poppins star expressing his admiration for the veteran campaigner who ran Hillary Clinton a close second for the Democratic nomination in 2016.

The outlook was dire for virtually everyone else.

Long before voting began, there was scepticism about Pete Buttigieg’s ability to win over a more diverse set of voters after strong finishes in overwhelmingly white Iowa and New Hampshire.

It was the opposite for Joe Biden, who struggled in Iowa and New Hampshire but looked to Nevada’s voters of colour to prove he still has a viable path to the nomination.

The two women left in the race, Elizabeth Warren and Amy Klobuchar, were fighting for momentum, hoping to benefit from a sudden surge of outside money from newly created super PACs.

Election 2020 Mike Bloomberg
Mike Bloomberg will enter the fray next month (Rick Bowmer/AP)

Billionaire Tom Steyer has invested more than 12 million US dollars of his own money on television advertising in Nevada.

The pro-Warren Persist super PAC, created in recent days, is spending more money in Nevada this week than any other campaign or allied outside group.

Persist, which has not yet disclosed any donors and cannot legally coordinate with Ms Warren’s campaign, has invested 902,000 US dollars this week in Nevada television on her behalf, according to spending data obtained by The AP.

That is more than Ms Klobuchar’s and Mr Biden’s campaigns have spent over the entire year.

New York billionaire Mike Bloomberg, who dominated the political conversation this week after a poor debate-stage debut, will not be on the ballot.

He is betting everything on a series of delegate-rich states that begin voting next month.

Election 2020 Trump
Many Trump supporters are confident that no Democrat will win in November (Patrick Semansky/AP)

“I think right now predicting who’s going to win here in Nevada would be a wild guess,” former Senate Majority Leader Harry Reid said in an interview.

“And if I were a gambler, which I’m not, I wouldn’t be betting on who’s gonna win here in Nevada.”

The political world, meanwhile, hoped there would be a winner at all.

Saturday’s caucuses are the first since technical glitches and human errors plagued Iowa’s kickoff caucuses.

Nearly three weeks later, state Democratic officials have yet to post final results.