No one expected a Florida Democratic primary like this

Florida Democrats will pick their choice of a presidential nominee Tuesday under circumstances no one could have predicted at the start of the year.

A race with one candidate plainly ahead. Campaigns with candidates almost entirely sidelined. A global pandemic seizing lives, U.S. markets and its politics.

Former Vice President Joe Biden’s hot streak and the fast-spreading coronavirus dramatically changed this race in the days leading up to Tuesday’s primary. Vermont Sen. Bernie Sanders has vowed to fight on after a second week of devastating losses, but his comeback strategy has been unquestionably altered by the outbreak.

Fears of contagion at large events has forced Sanders to shelve his most effective political weapon: his large, energetic rallies that can draw thousands of supporters. He has no planned appearances in Florida, the state with the most delegates at stake — 219 — of the four Tuesday primaries.

Biden has canceled his public events in the state, too, including planned rallies in Tampa and one in Miami on Monday, and he closed field offices. The AFL-CIO also nixed a planned presidential forum on labor issues in Orlando due to the virus. Biden and Sanders were supposed to attend.

Ione Townsend, chairwoman of the Hillsborough County Democratic Party, said a campaign without candidates is “a whole new ballgame” that puts “a lot more pressure on grassroots activists to deliver.” But Townsend, a nurse practitioner, preferred the two front-runners stay far from Florida.

“By virtue of age alone, they’re in a high-risk category,” Townsend said. “As far as I’m concerned, Bernie, stay in Vermont and Joe, stay in Delaware. Stay healthy because we can’t beat Trump if we lose either of you.”

Worries over the spread of the novel coronavirus are also causing logistical headaches for next week’s presidential preference primary. Election officials are searching for volunteers to replace anxious poll workers. Gov. Ron DeSantis ordered counties to move voting sites from assisted living facilities and nursing homes. The Florida Democratic Party has said the state isn’t doing enough to make sure people know their polling place may have moved.

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The realities on the ground have only raised the stakes of Sunday’s much-anticipated debate, the first time Biden and Sanders will go head-to-head on a stage. The debate was moved from Arizona to Washington, D.C., due to coronavirus concerns. There won’t be an audience.

Speaking Wednesday from his home state of Vermont, Sanders vowed to confront Biden over progressive fears that a moderate Democrat wouldn’t act boldly and quickly enough to stop medical bankruptcies, halt climate change, tackle student debt and end mass incarceration.

“Donald Trump must be defeated, and I will do everything in my power to make that happen,” Sanders said. “On Sunday night, in the first one-on-one debate of this campaign, the American people will have the opportunity to see which candidate is best positioned to accomplish that goal.”

If Sanders does have a last gasp, Tuesday has many delegates at stake to spur a turnaround. In addition to Florida, there are also major prizes to be won in Illinois, Ohio and Arizona. Biden leads Sanders by 151 delegates after last Tuesday’s primaries, and he’s ahead in Washington, which was still counting ballots Thursday. Biden is still less than halfway to the 1,991 delegates needed to clinch the nomination.

But Sanders is losing states that made him a viable presidential contender against Hillary Clinton in 2016. On Tuesday, Biden took every county in Michigan, a Sanders state four years ago, and in Missouri, which Clinton only narrowly won. Biden also handily won Mississippi, continuing his dominance of Sanders in the South and among black voters.

Florida is not a state Sanders was projected to do well in to begin with, and the state has broken further for Biden in the days since Super Tuesday, according to the latest polls. A University of North Florida survey of 1,500 likely voters showed Biden winning 66 percent of the vote to Sanders’ 22 percent.

Biden has tried not to appear presumptive about his chances while positioning his campaign for a general election race against President Donald Trump. Biden on Thursday delivered an address on coronavirus, a day after Trump did the same from the Oval Office. And Biden has already begun the effort to mend a party torn between its progressive values and its fear of another four years of Trump.

“I want to thank Bernie Sanders and his supporters for their tireless energy and their passion,” Biden said last week as results came in. “We share a common goal, and together we’ll defeat Donald Trump. We’ll defeat him together.”

It was only a few weeks ago Florida looked positioned to alter this race, a rarity for a state that often swings general elections but is almost never relevant in primaries. With Sanders leading, and the field divided between six candidates, the campaigns started looking at the Sunshine State as a defining date on the primary calendar. That was true even after Biden won South Carolina and his former rivals, ex-South Bend Mayor Pete Buttigieg and Sen. Amy Klobuchar dropped out and endorsed him.

The prevailing theories, based on polls and Biden’s deep ties to the Sunshine State, suggested Florida would provide a clinching win for the former vice president, or perhaps stall Sanders’ march to the nomination. The wildcard wasn’t a deadly virus, but the intractable spending of a billionaire ex-New York mayor.

“Florida. Florida. Florida," Biden Super PAC strategist Steve Schale texted a Tampa Bay Times reporter as Super Tuesday results trickled in favorably for his candidate.

Then that billionaire, Michael Bloomberg, dropped out and endorsed Biden. Sen. Elizabeth Warren ended her campaign as well — and didn’t endorse anyone. The clearing of the field changed the landscape significantly.

And then coronavirus hit.