(CNN) Bernie Sanders has a decision to make about his campaign now that his path to the Democratic presidential nomination has effectively closed and the coronavirus pandemic has thrown into question the timing of future primary elections.

But on Wednesday, when asked during a question and answer session with reporters what his time frame for making that decision was, Sanders did not want to discuss it, telling CNN's Manu Raju, "I'm dealing with a f**king global crisis."

Sanders, who was at work in the US Senate to address the pandemic, added that "right now I'm trying to do my best to make sure that we don't have an economic meltdown and that people don't die. Is that enough for you to keep me busy for today?"

Under normal circumstances, Sanders could do what he did in 2016: Stay in the race and spend the next three months pressuring his opponent, this time Joe Biden , to take progressive policy positions -- all the while amassing delegates who could turn into leverage as the party develops its platform. But the spread of the coronavirus has halted all in-person campaigning, preventing the Vermont senator from holding the large rallies that define his campaign. And the usual schedule of debates and primaries that would be opportunities for Sanders this time won't exist.

"We are assessing the state of our campaign," he said earlier Wednesday afternoon. "There's not going to be an election for another three weeks. We are talking to our supporters. Anybody who suggests that at this point we are ending the campaign is not telling the truth."

Aides to the Biden and Sanders campaigns confirmed to CNN Wednesday that their operations have been in "regular contact" since last week to discuss the pandemic.

But the outbreak has not stopped Biden's march toward the nomination. He notched three wins on Tuesday night to create a nearly insurmountable delegate lead against Sanders.

Joe Trippi, a longtime Democratic operative, said Biden's delegate lead "pretty much does slam the door on Bernie having any chance" to win the nomination.

That puts a lot of pressure on Sanders, he said. And that pressure is just increased by the spread of the coronavirus.

"Does it start to raise even more strength around the question about why go on," Trippi questioned. "Why continue to do this? What is the purpose at that point when it will be clear to everybody that the writing is on the wall?"

Some Democrats had speculated the delay of primary elections because of coronavirus could extend Sanders's presence in the race. But Tuesday night's results have started to increase the urgency some Democrats, most notably Biden supporters, feel about Sanders getting out.

"The race is not changing," said former Virginia Gov. Terry McAuliffe, a Biden supporter. "The math becomes virtually impossible and at that point nobody wants to look like they are stopping us from getting rid of an existential threat in the White House."

When asked about the difference between 2016 and 2020, McAuliffe said, "Here is the big difference: Donald Trump."

On Wednesday, there were signs of Sanders' world adjusting to the reality of the Democratic race.

His campaign has suspended all digital ads, and wasn't airing any television ads. Campaign manager Faiz Shakir said in an email to supporters that there was "no sugarcoating it, last night did not go the way we wanted."

Shakir said that after Sanders votes Wednesday in the Senate, "Bernie and Jane are going to get on a plane back to Vermont. Once there, they'll begin holding conversations with supporters to get input and assess the path forward for our campaign. We will keep you updated as those conversations progress."

On Tuesday night, a Sanders adviser told CNN that one of the Vermont senator's key considerations is, "If he ends his candidacy, will someone else step into the void and lead the movement? Is the best way to stay relevant by staying around for the rest of the race?"

Meanwhile, Biden's deputy campaign manager Kate Bedingfield argued in a memo Wednesday that "this primary is nowhere near as close as the 2008 and 2016 Democratic primaries," which were closer at this stage.

"In order to close the delegate deficit he faces, Senator Sanders would need to win every remaining contest by roughly 40 points," Bedingfield said in the memo.

Hanging over Sanders' decision is what the Vermont senator did four years ago in his race against Hillary Clinton.

Sanders kept the fight going even after his campaign effectively ended when Clinton won the New York primary in mid-April. Sanders leveled harsh attacks against Clinton throughout the fight, and the former secretary of state still believes that the long primary eventually hurt her in the general.

Nick Merrill, Clinton's spokesman, reflected on Sanders' current standing bluntly.

"I feel the same way about Bernie Sanders still being in this race as I do about people buying a 12-year supply of toilet paper," Merrill tweeted, a nod to American panic buying toilet paper in the face of the coronavirus.

The delegate math and the momentum in the race is much different than 2016. Sanders is now at a massive disadvantage, with Biden ahead with 1,086 pledged delegates earned to date to Sanders' 772, according to CNN's estimate as of late Wednesday morning. And while in 2016, Sanders had kept up momentum by delivering out-of-nowhere victories in states like Michigan, this year Biden is showing no signs of weaknesses anywhere on the map and states like California, which voted late in 2016, have already been counted.

The delegate math is daunting: To get to the 1,991 delegates necessary to win the nomination, Sanders would need to win 1,219 more delegates. But there are only 1,668 delegates available in the states that haven't voted yet, and another 349 that CNN hasn't yet allocated from states that have already voted but where results are still being tallied and finalized.

Because the Democratic Party's rules that divvy up delegates on a proportional basis make it difficult for a single state to deliver any candidate massive gains, Sanders would not only need to win in most of the rest of the states on the map -- he'd need to blow Biden out.

And any chance for that won't come for weeks as election officials across the country delay their primaries.

Ohio was scheduled to have its primary Tuesday night, but the state's health director ordered the polls closed because of coronavirus. The state's secretary of state is now in the process of trying to reschedule the contest for June 2.

Georgia's contest, which was meant to be held next Tuesday, has been moved to mid-May, while officials in Maryland, Louisiana and Kentucky -- all primaries that were meant to take place in either April or May -- have moved their contests to June.

Pressure to delay primaries is now on officials in Alaska and Hawaii, where contests are slated to be held on April 4, and in Wisconsin, the next major prize in the Democratic primary, where voters are slated to cast ballots on April 7.

This story has been updated with additional developments Wednesday.