While he has been off the trail over the past week, Mr. Biden has begun to run something like a Rose Garden campaign, or whatever the equivalent is for someone who is not already the president: He appointed a public health task force and unveiled a detailed policy agenda for addressing the coronavirus in a formal speech on Thursday. Over the weekend Mr. Biden held a phone call with Senator Elizabeth Warren of Massachusetts, his progressive former rival, and endorsed liberal policies on higher education and bankruptcy reform in an effort to woo the left.
It is not clear how long Mr. Biden and Mr. Sanders might be kept from campaigning altogether. Both men are confronting the likelihood that they will not be able to hold traditional campaign events until well into the spring, at the earliest, and even the possibility that the summer nominating conventions could be endangered by the imperatives of fighting the coronavirus.
The elections on Tuesday offered new evidence of just how difficult it had become to hold any semblance of normal primary elections. There were reports in multiple states of election workers not showing up at the polls; even in densely populated and heavily Democratic areas, like Miami-Dade County in Florida and Cook County in Illinois, voter turnout appeared low on Tuesday morning.
Most of all, the frenzy of sudden, and sometimes contradictory, last-minute announcements in Ohio underscored the potential for outright chaos at the polls. Gov. Mike DeWine, a Republican, declared late on Monday that he would not allow Ohio’s primary to go forward.
After an initial setback in court, Mr. DeWine’s state health director issued an order closing the polls as a health emergency, and early on Tuesday morning a state court allowed that decision to go forward. It was not immediately clear how Ohio would go about reviving the primary, but Mr. DeWine said on Tuesday that it would have been irresponsible to proceed with in-person voting this week.
“This is a gathering of people, and what we’ve tried to do is explain to Ohioans we cannot have large gatherings,” Mr. DeWine said of the primary election, in a television appearance on Tuesday.
Election officials in the other three states voting on Tuesday conceded that the coronavirus was a cause for concern but said that they were taking steps to sanitize the polls. And in perhaps a bleak reflection of the country’s present condition, Katie Hobbs, Arizona’s secretary of state, warned that there was “no guarantee that there will be a safer time to hold this election in the near future.”
“The longer we wait, the more difficult and dangerous it could become,” she said.