With the coronavirus outbreak spreading across the nation, Tuesday’s presidential primaries in Arizona, Florida and Illinois may well be the last ones held for the next couple months.

Ohio’s primary was also scheduled to be held Tuesday – but state officials used emergency powers to postpone the contest hours before the polls were set to open. Primaries scheduled for next Tuesday in Georgia, April 4 in Louisiana, and May 19 in Kentucky already have been pushed back to later dates.

Maryland Gov. Larry Hogan also announced on Tuesday that his state's April 28 primary is being postponed until June 2. Democratic Party officials in Puerto Rico – which would hold its contest on March 29 – are seeking a delay as well.

PRIMARIES BEING HELD IN THREE BID STATES DESPITE CORONAVIRUS

More delays are likely to follow for states scheduled to hold contests in the coming weeks.

In Alaska, which is scheduled to hold its primary on April 4, the state Democratic Party urged voters to cast ballots by mail, tweeting: “If you were a registered Democrat by February 18, you should have your presidential primary ballot in the mail! Don't forget to follow the instructions, and mail it back postmarked by March 24!”

These abrupt moves come with the country facing an unprecedented crisis as the coronavirus pandemic has caused millions of Americans to self-isolate in their homes in hopes of stemming the spread of the outbreak.

After the Centers for Disease Control (CDC) urged against any gatherings of 50 people or more, Ohio Gov. Mike DeWine stressed on Monday that “we cannot conduct this election tomorrow.”

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Down the road – but also very much up in the air – are the biggest political gatherings of the year: the Democratic and Republican presidential nominating conventions. These two marquee political events are massive operations that take years of planning and have huge economic impacts on their host cities. But just like everything else in this world turned upside down by the virus that causes COVID-19, they may be in jeopardy.

“The plan is to still move forward but this is obviously a fluid situation and we have to be prepared for everything,” a Democratic official with knowledge of planning for the Democratic National Convention told Fox News. “We’re going to stay in contact with relevant officials on the local, state, and federal level.”

The convention is scheduled to be held July 13-16 in Milwaukee, Wis. Asked if there are conversations underway about pushing back the date of the convention or holding a more limited event, the official said: “We will have plans in place to do something differently if need be, but the plan right now is to move on as scheduled.”

The GOP has a bit more breathing room. The Republican National Convention is scheduled to be held Aug. 24-27 in Charlotte, N.C.

“As we move forward with planning, we remain in communication with local, state and federal officials and we will continue to closely monitor the situation and work with all stakeholders and health authorities to ensure every necessary precaution is taken into account,” 2020 Republican National Convention communications Blair Ellis told Fox News.

She said that “we prioritize the health and safety of delegates, media, guests, community members and staff.”

But there’s a more immediate concern than the national conventions.

Officials have already postponed some state party conventions, where the delegate process initiated during the primaries and caucuses continues and delegates who will represent their states at the national conventions are chosen.

DNC Chairman Tom Perez sent state party chairs an email last week saying that the national party’s delegate selection team has been in contact with states that need to make changes to their delegate selection process due to the pandemic to ensure the nominating process will “continue without major interruptions.”

Longtime Democratic National Committee member Kathy Sullivan – a veteran of the Rules Committee – noted that some states will need a waiver to change their approved delegate-selection plan. But she said “that’s not going to be a big deal. Everybody understands this is an unusual situation. … I think with the technology nowadays, these sorts of things can be handled.”

A Democratic Party official acknowledged that “we are in uncharted waters right now” but emphasized, “what we have to do is stay in contact with everyone and be flexible, given the situation.”

The potential freezing of the primary calendar comes as former Vice President Joe Biden – thanks to sweeping victories the past two-and-a-half weeks – has cemented his position as the unrivaled front-runner and has taken a commanding lead over Sen. Bernie Sanders of Vermont in the all-important race for convention delegates.

At the same time, Biden’s seen a tidal wave of support and endorsements from current and former members of Congress, governors and state lawmakers and party rainmakers – as centrists, moderates, and the party establishment have all coalesced around the former vice president in hopes that they’ve found the contender who can take out President Trump in November’s general election.

Heading into Tuesday’s contests, Biden held a 153 pledged delegate lead over Sanders. And while he’s expected to pad that lead in Arizona, Florida, and Illinois – where public opinion polls indicated he held large leads over Sanders – the former vice president will still be far short of the 1,991 pledged delegates needed to clinch the Democratic nomination.

That’s raised questions and concerns that Sanders – even if he suffers three more defeats on Tuesday – may stay in a contest that is being frozen in place by the global outbreak of the virus.

On the eve of this week’s contests, Sanders in an email to supporters stressed that “this primary is far from over.”