In Erie County, Pa., either Joe Biden or President Trump is showing up every week now, and the anxiety level is through the roof.

There’s fear of neighbors: On Election Day, self-appointed guardians armed with assault weapons plan to take up positions outside local polling places. There’s fear of outsiders: A Ku Klux Klan group from out of state recently dropped racist fliers on the driveways of some homes with Biden signs on the lawns. And there’s fear of what’s coming Nov. 3: The county sheriff doesn’t have nearly enough deputies to keep eyes on all 149 polls.

In one of the most important battlegrounds in one of the most critical swing states in the 2020 presidential race, the Republican county chairman, Verel Salmon, 73, sees “passion like never before in my lifetime, for good and bad, and I started with ‘I Like Ike.’ I don’t think I’ve heard a single optimistic thing this year.”

“With every day, the tension gets higher,” agreed Jim Wertz, the county’s Democratic chairman. “We’re asking the county to respond to any acts of intimidation.”

But for all the worry about Election Day disruptions, Wertz, Salmon and many of the county’s elected officials say they are confident this election will work. They trust the sheriff to handle any unrest or intimidation, and they think the voters will make themselves heard at the ballot box, not in the streets.

“I tell Erie County people, ‘Relax, there’s checks and balances and a competent staff,’ ” Salmon said. “It’s America — we’re always arguing about basics. This is another grand experiment.”

With two weeks left in a campaign many fear will feature unprecedented efforts to manipulate, suppress and challenge votes, much of the nation is on edge. Will Election Day go smoothly, without intimidation of voters? How long will it take to process the flood of mail-in ballots coming from people seeking to avoid exposure to the novel coronavirus? And when will the nation know who won?

Much attention has focused on the endgame in Washington and rarely invoked laws that govern how Congress and federal courts decide which contested votes ultimately count. But before any challenge reaches the nation’s capital, election officials in 3,141 counties must tally local ballots, a process that could be unusually lengthy this year, creating an opportunity for those who want to question or alter the outcome.

Nowhere are those issues more pressing than in Erie County, a Rust Belt relic with harsh winters and a lovely lakefront. Pennsylvania law forbids counting mail-in ballots — or even opening the envelopes — before Election Day. The winner may not be known for days after the polls close, with a Nov. 23 deadline for reporting the final count to the state.

And Erie is very much up for grabs: Biden visited this month, appearing in front of a union hall where he blasted Trump for the uneven economic recovery. Trump, who has held two rallies in the city since taking office, plans to visit again Tuesday evening in hopes of reprising his 2016 performance, when his appeal to nostalgia, resentment and the desire to shake up Washington made him the first Republican to carry the county since Ronald Reagan in 1984.

Four years ago, Pennsylvania produced Trump’s second-smallest victory margin — only Michigan was closer. In Erie, which had almost 20,000 more registered Democrats than Republicans among its 280,000 residents, Trump beat Hillary Clinton by just 1,957 votes.

This year, Trump has a 50 percent to 47 percent lead in Erie and other western Pennsylvania counties outside Allegheny, a Democratic stronghold that includes Pittsburgh, according to the most recent Washington Post-ABC News poll. In 2016, Trump won the area by 29 points.

The people in charge of making this election run smoothly say they can feel the difference.

“The anxiety is definitely higher than I’ve seen,” said Douglas Smith, Erie’s elections chief. “Our office has become a call center, just constant emails and calls and people coming to vote at the counter. We’re hopping.”

“This is an election like no other,” said Sheriff John Loomis, whose computer screen tells a story of nervous anticipation — emails and Facebook pages that reek of intimidation, that allude to “unrest or that some individuals might want to slow the voting down.”

“The worry is the unknown,” Loomis said. “Nobody knows how everybody else is going to react, whichever way it goes.”

In a county of small towns where families trace their roots back for generations, Election Day has always been a kind of secular holy day.

“Usually, you go to vote, you have a nice day, you buy some bread from the ladies’ auxiliary at the polling place,” said Brian Shank, a Republican county council member who organized a road parade for Trump last month.

“This will not be a normal Election Day,” Shank said. “This year, you have people who want to intimidate.”

Shank, a former corrections officer and DJ, gained prominence in the county in 2012, when he and other gun advocates wore firearms — in his case, a holstered .45 — into a city park to assert the right to carry openly. But he said there’s a right time and place for everything.

“I am not a big fan of the AR-15 slung across your back,” he said. “Optically, it just doesn’t sell well.”

On Election Day and through the uncertain days that follow, Justin Dillon, a pro-gun activist who lives in Erie, said he and other armed members of his Open Carry Pennsylvania group “will be monitoring to make sure people are safe and businesses aren’t looted. There’s little townships in the county that don’t have adequate policing to handle riots. Citizens at some point have to take matters into their own hands.”

Dillon and his fellow open-carry advocates say they may position themselves outside voting centers that don’t normally see much police presence. The idea is to support Trump and assure no one interferes with the election, they said, not to confront law enforcement or inhibit voters.

“People are going to be around while votes are cast as a statement that they’re supportive of Second Amendment rights,” Dillon said. “We really don’t want to scare people off from voting in person because that’s the most secure way to vote.”

The county’s elected officials, Democrats and Republicans alike, agree that a polling station is no place for a show of force. But no one has figured out how to stop it. Loomis has just 42 deputies to cover 149 polling places, and it’s not clear they could do much about armed observers anyway. Maybe just ask them to respect the sanctity of the day and back away.

“They’re asserting their legal right to carry,” Loomis said. “But for people who are not carrying weapons, that can be intimidating. Everybody knows right now we’re not living under normal circumstances.”

The potential exists for a clash of rights, said Smith, the elections chief: “If there are 20 armed people outside a polling place who are just standing around being pleasant, that’s not violent. But certainly some people would find that intimidating. Everybody’s on heightened alert.”

That alert only spiked when several county residents reported finding plastic bags on their driveways or doorsteps filled with racist fliers saying that Black Lives Matters activists are “running wild in the streets,” that a Democratic victory will “assure complete destruction” of constitutional rights and that “Blacks owe Whites an apology.”

Some of the letters were anonymous; others bore the signature of the Loyal White Knights, a Ku Klux Klan group based in North Carolina. The organization’s leaders did not respond to calls seeking comment.

Shank, the county councilman, said he hopes Dillon and other open-carry advocates will reconsider bringing their guns to the polls. But he understands that passions are running strong.

“I can boil this all down to one word — angry,” he said. “This country is angry, and I don’t know why. We have a great country. We have all these freedoms people in other countries just don’t have.”

For all the talk about intimidation, few in Erie expect violence. On the contrary, there’s a sense that the anxiety reflects the hopped-up national news narrative more than any homegrown effort to disrupt the vote.

The nightmare scenarios voters hear about on TV and online have combined with the coronavirus to create doubt and worry, said Greg Hayes, a Republican candidate for state legislature and owner of a flight school in Erie.

Hayes anticipates “a monstrous delay in counting, and that will make people’s imaginations go wild,” he said. “The mind-set of people has really changed because of this covid stuff. They’re locked in at home, especially older voters who are very easily persuaded that there’s going to be a problem. They’re watching TV and hearing stories from around the country about ballots disappearing or people receiving two or three ballots. The local confidence in the election is very low.”

It’s not Election Day that worries most county officials. It’s the next stage — the count.

This spring, in the primary, it took 10 days for the county elections office to count about 30,000 mail-in ballots. With more than 70,000 expected this time around, Erie officials have hired up, going from eight to 15 workers opening envelopes and feeding ballots into the tallying machines. They’ve added hours — counting will start each day at 7 a.m., three hours earlier than during the primary. And they’ve added machines, including a second high-speed scanner to read ballots and an automatic letter opener that can unseal 20,000 ballots per hour, Smith said.

Each envelope takes about 90 seconds to scan and prepare for counting, work that Smith would love to do ahead of time. But a state law prohibits opening and preparing mail-in envelopes for tallying before Election Day and counting those ballots before the polls close. So far, neither lawmakers nor the courts have approved a change to the rules.

All that work will take place in counting rooms jammed with people trying to oversee every move. Salmon said Republicans will deploy an army of poll watchers, lawyers and count observers. Wertz said Democrats will do the same, with more than 200 volunteers around the county and two shifts of observers in the counting rooms.

The scene can look chaotic and crowded, but it works, Republicans and Democrats agree. “We do everything in our power to keep each vote, even if the signature is sloppy and it’s changed over 15 years,” said county councilman Shank, who acts, along with his fellow council members, as Erie’s board of elections.

Still, every day a final count is delayed could undermine trust in the outcome, many in the county say.

“The integrity of the vote is going to be questioned,” said Dillon, the open-carry activist. “It doesn’t make sense that we have to wait weeks before learning who won.”

Despite the drive to accelerate the count, “they’re so far from having the resources they need, it’s not even funny,” Hayes, the Republican legislative candidate, said after meeting with local police chiefs and election officials. “If we get an answer within three weeks, I’ll be surprised.”

Prepare to be surprised, Smith said. He hopes to finish by Nov. 6, the Friday after Election Day, well ahead of the Nov. 12 deadline by which he must report unofficial results to the state and the Nov. 23 deadline by which county elections boards must certify final, official results to Pennsylvania’s secretary of state.

In nightmare scenarios that climax with Congress and the Supreme Court playing a role in picking the next president, things go kablooey in the final stage of each county’s role — when the county formally submits its tally to the state, which uses that tally to choose electors, who are then sent to Washington pledged to vote for the candidate who won their state’s popular vote.

If Erie — or any county — misses the deadline, the Republican-controlled state legislature could declare that Pennsylvanians failed to complete their vote, allowing lawmakers to choose electors on their own. The Republican majority presumably would pick electors pledged to Trump.

Whether the state’s Democratic governor, Tom Wolf, could block that choice or pick his own slate of electors is a matter of dispute even among election lawyers.

But if Erie is representative of Pennsylvania’s 67 counties, Smith and other top officials don’t see how this election could open the door to such extraordinary maneuvering in Harrisburg, the state capital.

“The scrutiny will be on a grand scale, but I don’t see any legal foundation for that fear,” Smith said. “We report the results to the state Department of State, and they report the results and appoint the electors. There will be no legal role for the legislature.”

Still, some Democrats worry Republicans “want to run out the clock and appoint electors based on their gerrymandered majority,” as Ryan Bizzarro, a Democratic state legislator from Erie, put it. Republicans deny any such intent.

“We are every bit as divided as Washington,” Bizzarro said, pointing to a recent effort by Republicans to grant the legislature power to subpoena ballots and elections officials even as the count progresses. Republicans withdrew that proposal, but mutual suspicions have not abated.

In Erie, both sides contend they will eke out a narrow win, and both sides say they’ll do it cleanly, if under an unusually powerful microscope of inspection.

“If Trump wins, a lot of Democrats will say ‘fake, fake,’ ” Shank said. “If he loses, there’s going to be a lot of noise about mail shenanigans. But I truly, truly believe the system works. It’s going to be smooth.”

Smith, the elections chief, said he probably won’t get a full night’s sleep for several weeks. But he also isn’t expecting any nightmares.

“All we can do is plan and be ready and take it as it comes,” Smith said. “I have faith, based on how prepared we are and our added staff and equipment. I do have faith that it’ll work out.”