Election officials are in a difficult situation. They want to protect the physical health of both voters and poll workers, but they’re also tasked with preserving the democratic process. Georgia and Louisiana recently postponed their primaries, and Ohio—which was set to vote today—canceled in-person voting over concerns about the coronavirus. But Arizona, Illinois, and Florida are carrying on mostly for logistical reasons, officials have said. They’ve secured polling places, hired poll workers, mailed out absentee ballots, and negotiated with the national parties about timing. “To upend all that is a pretty big step,” especially when it’s still not clear when it will be safe to reschedule, says Barry Burden, the director of the Elections Research Center at the University of Wisconsin at Madison. “I think it makes sense to move ahead and just do it in an imperfect way.”

But why, I asked Burden, can’t states just mail everyone ballots and give them a few weeks to mail them back? The answer, he said, is that many election dates are written into state law, and an all-mail system would require infrastructure that doesn’t already exist in many places. “We should be cautious about viewing vote by mail as a cure-all,” he said. “In such a tight time frame, it’s just not going to work for a lot of states.”

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Ahead of today’s voting, election officials in Arizona, Illinois, and Florida encouraged people to send in absentee ballots or vote early at designated sites. But while officials predict that some regular voters will not show up today, they still expect that many will vote in person. So their focus has shifted to cleanliness. Officials in each of the three states are preparing to arm polling sites with sanitation supplies. In most cases, that means providing gloves for poll workers, hand sanitizer for voters, isopropyl-alcohol wipes to clean the voting machines between each use, and disinfectant wipes for tables and other surfaces. Officials are also encouraging voters to bring their own pen to fill out forms, and they’re training poll workers in proper equipment-cleaning and hand-washing techniques.

The mere threat of contracting the coronavirus has already rattled the election process in the three states voting today. State officials have had to close polling locations with a high population of vulnerable people, such as nursing homes and other care facilities. Poll workers, many of whom are elderly and therefore more susceptible to the virus, will be putting their health at risk if they show up for a 12- or 14-hour shift on Election Day. “For people over the age of 60 or people who have underlying health conditions, I would not volunteer as a poll worker,” Watson said. Ohio Governor Mike DeWine echoed that concern late last night when he announced the closure of the state’s polls. “To conduct an election tomorrow would force poll workers and voters to place themselves at an unacceptable health risk of contracting coronavirus,” he said in a statement.