Five questions on the US Democratic primaries

Four US states had been scheduled to hold Democratic presidential primaries amid a global outbreak of the novel coronavirus – but leaders in Ohio have called off their election, citing public health concerns.

Arizona, Illinois and Florida are going ahead with plans to vote.

Here are five questions ahead of the vote:

– Will the elections take place?

Nothing is certain in the age of the coronavirus.

Three states scheduled to vote after Tuesday postponed their primaries. Ohio has scrapped its vote, while Arizona, Florida and Illinois vowed to push ahead.

Voting clusters large numbers of people together at polling stations often staffed by volunteers and older workers – and this is exactly the dynamic medical experts want to avoid right now.

On Sunday, Vermont senator Bernie Sanders suggested delaying Tuesday’s votes. And on Monday night, Ohio’s Republican governor Mike DeWine agreed.

The state’s health director declared a health emergency and ordered the polls closed.

– Who will vote?

With voting still on in some states, the question moves on to turnout. This has surged in recent Democratic contests as a wave of suburban voters helped catapult former vice president Joe Biden to his solid lead in the race.

All of the states allow early voting, so there is a good chance that many people have cast ballots remotely by mail. Still, it would be no surprise if turnout drops significantly.

– Can Biden continue his momentum?

Joe Biden vaulted to his front-runner position on March 3, also known as Super Tuesday, and has never looked back.

He added to his advantage in last week’s primaries, besting Mr Sanders in key states like Michigan and Missouri and dominating in Mississippi, where Mr Biden’s base of black voters gave him a massive delegate haul.

It is exceedingly difficult for Sanders to catch up with Biden at this point because the Democratic Party’s rules award delegates proportionally. That means that even if the Vermont senator wins the states up for grabs on Tuesday, he would split their delegates with Mr Biden.

Mr Sanders is in a tough position, but he has made one noteworthy addition to his coalition — Latinos, who powered Sanders to wins in California and Nevada.

Latino voters tend to be younger, and Mr Sanders’ support is largely youthful. But some Democratic Latinos are angry at the heavy pace of deportations under the Obama administration.

Mr Biden has taken steps to make up for that. He has joined Mr Sanders in a pledge to suspend deportations for his first 100 days.

Three of the four states that had been scheduled to vote Tuesday have sizeable Latino populations, and Florida, which is heavy with Cuban immigrants, may be an especially bad match for Mr Sanders, a self-described democratic socialist.

The elections were already well under way with early voting before the full force of the coronavirus outbreak hit the US. But that is not true of the half of the states that have still yet to cast ballots.

Some could shift to postal-only contests; others, like Louisiana, have delayed their contests until June 22, after the traditional close of the nominating period.

It is unclear that there will be many more days of large-scale voting.

Although Mr Biden has assembled a strong coalition, there is still a significant split as liberal and especially younger voters overwhelmingly stick with Mr Sanders.

If the primary effectively ends on Tuesday, the question remains over whether these voters can be brought back into the fold. Mr Biden may have to turn his attention to President Donald Trump in the general election in the autumn without significant chunks of his party.