AMNA NAWAZ: Midterm election season culminates on one important Election Day, but, in many states, voting is already under way.

For the local officials who run elections, the work started even earlier.

Liz Landers has a closer look at how they prepare for voting and why they say you should trust the process.

BRIAN MCKENZIE, Davis County, Utah, Clerk: We're testing the overvote function of the machine to make sure it accurately identifies those.

LIZ LANDERS: Before a single real ballot is counted in Davis County, Utah, workers run stacks of pre-marked test ballots through the machines.

Some are marked wrong on purpose.

It's called logic and accuracy testing, and it confirms the machines count ballots correctly and catch errors like a voter picking too many candidates.

Utah is one of a handful of states that votes mostly by mail.

County clerk Brian McKenzie explains the path a mail ballot takes.

BRIAN MCKENZIE: This is Mickey Mouse and Donald Duck, that their envelopes have come in, right?

LIZ LANDERS: Every envelope carries its own bar code.

If a voter needs a replacement ballot, the old code is canceled, a check McKenzie says keeps anyone from getting more than one ballot.

Return ballots are picked up by at least two election workers, logged and brought here under around-the-clock video surveillance.

Each envelope is scanned, date-stamped, and photographed.

Workers compare the signature to as many as five on file, all that before a machine even opens the envelope.

BRIAN MCKENZIE: That machine creates that separation from your personal identifiers and anything that you voted, maintaining your constitutional right to a secret ballot.

LIZ LANDERS: Ballots move through the process in batches of 200, counted at every step.

Vote tallies are loaded onto encrypted memory sticks.

BRIAN MCKENZIE: Nothing is wireless.

Nothing is Web-based.

It's all physical, manual process to transfer that data from one place to another.

LIZ LANDERS: McKenzie's first election in 2004 used punch cards.

Now he's the county's clerk elected in 2022.

Over that time, the job has gotten a lot more public.

BRIAN MCKENZIE: Early years, it was a successful election if you never made the front-page news, right?

But there is a lot more focus on it.

There's a lot more engagement to it.

LIZ LANDERS: This year, that focus included a fight in Washington over voting by mail, which President Trump has tried to curtail.

At his direction, the United States Postal Service announced new rules to regulate mail ballots before the Supreme Court stepped in last month to block it.

The uncertainty had McKenzie's team drawing up backup plans.

He says the big risk is always change that comes too close to an election.

BRIAN MCKENZIE: I have found that, with enough time and information that, yes, our voters do adapt and they do adjust.

The concern is when it's short.

Short notice, significant changes, that creates disruption.

That creates question.

And when you have questions like that creates doubt.

When people have doubt, they disengage.

JOSEPH KIRK, Election Supervisor, Bartow County, Georgia: Well, crews come in, pick up everything, deliver it to the polling place.

LIZ LANDERS: Doubt is what also worries Joseph Kirk.

He's the election supervisor in Bartow County, Georgia, northwest of Atlanta, and he's readying the machines that will go out to polling places.

JOSEPH KIRK: Seal it up.

LIZ LANDERS: He says the bigger danger may not be someone changing votes.

JOSEPH KIRK: There are so many ways to cast doubt on the election through that process, and I think that's the true danger.

I don't know that anybody is going to try to, like, say, hack the voting system and change the votes.

But they might try to convince people it's not worth voting, that there's no need to participate, it's just a show game.

LIZ LANDERS: Defending those systems against foreign governments is another matter.

Kirk says some of the federal help his office once relied on has all but evaporated since the Trump administration has scaled back the agency that oversees election security.

JOSEPH KIRK: Maybe the easiest way to describe the need is, it takes a nation-state to fight a nation-state.

I have a great I.T.

director, but he can't fight China or any other country, and he shouldn't be expected to.

And we had a lot of resources available to us through the federal agencies that either are not available anymore or available in different ways that are hard to participate in.

LIZ LANDERS: In Western Colorado, Mesa County's Republican clerk, Bobbie Gross, is trying to build trust by bringing the public inside.

BOBBIE GROSS, Mesa County, Colorado, Clerk and Recorder: We have started since 2023 bringing the public in for election tours and also doing a lot of community engagement, going out and speaking with different organizations.

And we just really focus on elections and building that trust within our community.

LIZ LANDERS: That trust took a hit here.

After the 2020 election, the county's former clerk, Tina Peters, allowed unauthorized access to its voting equipment.

She was trying to prove fraud claims that were unfounded.

She was convicted and sentenced to nearly nine years in prison.

This spring, after pressure from President Trump, Colorado's governor commuted her sentence.

She was released in June and has kept pushing unproven claims that Colorado's elections aren't secure.

Gross says trusting an election doesn't depend on liking how it turns out.

BOBBIE GROSS: There's never an election where you voted for everything you wanted and everything won, right?

It just doesn't happen.

We're going to be disappointed in outcomes, but we need to be able to trust those outcomes and know that there's nothing nefarious going on behind the scenes.

LIZ LANDERS: Back in Utah, ballots go out to voters about three weeks before Election Day.

McKenzie says the speed of the count isn't how he measures success.

BRIAN MCKENZIE: Of course, we'd love to have ballots counted just as quickly as possible and all of that, but ultimately it comes down to the voter experience, making sure that that's a great experience for our citizens.

LIZ LANDERS: With Election Day around the corner, local officials across the country hope more transparency will mean more trust.

For the "PBS News Hour," I'm Liz Landers.