Even before the coronavirus pandemic, Tina Barton knew counting mail ballots would become a problem.
Barton is the city clerk of Rochester Hills, Mich., and after a 2018 state constitutional amendment meant that all voters in Michigan could vote absentee without an excuse, she began sounding the alarm: Election officials were going to start getting a lot more mail, but they weren't being given any more time to deal with it.
A local election that she administered last year, after the new law went into effect, saw more than 80% of voters cast an absentee ballot.
"Knowing that people were taking advantage of this new opportunity, we started projecting — where would this place us in 2020?" Barton says. "At this point, we still have no idea there's a pandemic about ready to hit us."
The pandemic has only accelerated the nation's move toward more mail voting, with as many as half of all votes coming through the mail nationwide.
And now the pressure is on local election officials to count those votes — quickly and accurately.
That task is tougher in a number of swing states where laws haven't adjusted as quickly as voting behavior: most notably Pennsylvania, Michigan and Wisconsin, all states that will be key to President Trump's reelection hopes and all states with thin-enough margins that a small number of outstanding ballots could decide a race.
Mail ballots take more time and resources to process than in-person votes. Election officials need to verify signatures, open envelopes, separate ballots from secrecy sleeves and sort them — all before they're fed through tabulators.
None of those steps is overwhelming until they are scaled exponentially, says Kathleen Hale, the director of Auburn University's Election Administration Initiative. She says to think of it like the holiday season, and receiving gifts and writing thank-you notes.
"Maybe you would normally receive 10 gifts and write thank-you notes for each of the gifts. Only now you're going to receive a thousand of them," Hale said. "The technical steps aren't terribly complicated — there is simply a long sequence that has to take place."
In more than two-thirds of states, officials can start that work in the weeks leading up to Election Day — they just can't release any results. But until recently, under Michigan law, Barton wasn't allowed to start that work until Election Day.
"What we would do then is start at 7 a.m., and basically you had to work until the job was done," she says, "whether that was 11 o'clock at night or 4 o'clock the next morning."
Many election workers are in their 70s, and Barton would sometimes feel uncomfortable about sending them to drive home after finishing up a 20-hour day — not to mention, wondering whether these constraints were affecting their performance.
"They're sequestered in a room. They have to go to the restroom in groups of two. They can't have any connection to the outside world," she says. "And to think that the quality of the work may not be diminished, I think, is irresponsible."
She, other local clerks and state election officials lobbied the Michigan legislature for more time, and they got it. At least a little. A new law passed this month means they can now open the envelopes and sort the ballots a day earlier.
"I wish we could do more, but I'll be honest with you: It took us a year to get to this point. So I'm going to take this as a victory," she said. "That is one process that I can do 30,000 times on Monday that I don't have to do on Tuesday."
But some other swing states haven't been so lucky.
Republican legislatures in Wisconsin and Pennsylvania have not changed their election laws despite expecting a huge surge in mail ballots.
Pennsylvania Secretary of State Kathy Boockvar talked with NPR in June about the problem.
"You could do so much of the process weeks before. And that's what a lot of other states do," she said. "So we're hoping to work with the legislature to make that change before November."
So far there has been no movement.
Clerks in both states will have to wait until Election Day to do most of the processing work. And if margins are close in either state, that could potentially mean it takes longer to know who has won the presidency.
Trump has tried to portray that possibility as a national catastrophe or a sign of "fraud like you've never seen," as he said in last month's debate.
"We won't know [who won]," Trump said. "We might not know for months, because these ballots are going to be all over."
That sort of talk is putting more pressure on local election officials, says Rachel Rodriguez, an election official in Dane County, Wis., even if the claims aren't true.
"If we don't have results at 9 or 10 p.m. on election night, that doesn't mean there's anything nefarious going on. It doesn't mean that there's any sort of conspiracy," Rodriguez said. "It doesn't even mean that there's a problem. It just means that clerks are still trying to count ballots and they are trying to make sure that everybody's votes are counted."
Voting experts, as well as national security officials, agree that a wait for results isn't a problem. The results people see on their TVs on election night are media projections, not official results, anyway. And it always takes election administrators time after Election Day to finish their tabulations.
But problems emerge when people try to sow doubt in the results because they are taking time to be calculated.
"Foreign actors and cybercriminals could exploit the time required to certify and announce elections' results by disseminating disinformation that includes reports of voter suppression, cyberattacks targeting election infrastructure, voter or ballot fraud, and other problems intended to convince the public of the elections' illegitimacy," wrote the FBI and the Department of Homeland Security's cybersecurity branch in a bulletin last month.
Some counties, like Lehigh County in Pennsylvania, have purchased new equipment to process ballots faster.
The county purchased two high-speed envelope openers to speed things up on Election Day, Chief Clerk Timothy Benyo told NPR, after the motor on one of its old machines died as the county was counting ballots during the primary, causing workers to open thousands of envelopes by hand.
Other jurisdictions have beefed up staffing. In Detroit, the mayor is closing much of the city's services for two days so city staff can help with absentee-ballot processing.
But there will still almost certainly be some logjams created by the rules. States have rapidly expanded voting options to respond to the pandemic, says Auburn University's Hale, but their legislatures haven't kept up in these cases.
"Every state's laws about all of the different pieces of the [elections] process, they all hang together," Hale said. "And so changing one piece usually means that changes need to be made to other pieces, to have the system work the way it was intended."
NPR correspondent Pam Fessler contributed reporting to this story.