The fight over which mail ballots should be counted during this year’s general election is already well underway.

Many states allow ballots that are postmarked on or before Election Day to be counted — even if they arrive after in-person voting has ended.

But the Trump campaign and the Republican National Committee argue this practice violates federal law, and they’ve filed multiple lawsuits aiming to disqualify ballots that arrive after Election Day.

One key state where Republicans are challenging these return windows is Nevada, whose state lawmakers created a universal mail voting program in 2021.

The numbers of ballots at issue are substantial.

During the 2020 election, Joe Biden beat Donald Trump in Nevada by about 33,500 votes.

In the 2022 midterms, in Clark County alone — the county where Las Vegas is — state officials say about 40,000 valid ballots came in after Election Day.

Nevada’s mail ballot program

Kerry Durmick — the Nevada state director of All Voting is Local, a group that advocates for expanding voting access — said the state’s absentee program has increased voter participation nearly across the board.

“If you’re an active Nevada registered voter, you automatically receive a vote-by-mail ballot,” Durmick said. “So it’s completely changed how our elections work and run.”

Durmick said every county in Nevada now runs a typical in-person election and automatically sends out mail ballots to all of its active voters.

Per state law, election officials can count mail ballots that are postmarked on or before Election Day and are received by 5 p.m. on the fourth day after Election Day.

Durmick says Nevada lawmakers created this window for turning in a ballot in case there are issues with the Postal Service.

The other reason, they said, is to give voters some wiggle room. Durmick says a lot of voters don’t remember to turn in their ballot until Election Day.

“It could happen to any single eligible Nevada voter,” they said. “It really isn’t centered around one community or one age group in any way.”

Republican pushback

The Trump campaign and the Republican National Committee, however, say this practice violates federal law. In a lawsuit filed against Nevada elections officials, they argue ballots that arrive after Election Day should be invalid.

“Congress has established a uniform, national day to elect members of Congress and to appoint presidential electors,” the plaintiffs wrote. “Nevada effectively extends Nevada’s federal election past the Election Day established by Congress.”

Christina Bobb, senior counsel with the RNC, said accepting late-arriving ballots is also an election security issue.

“The way to make the election the most secure is that everybody has the same finish line,” she told NPR. “And if the finish line gets extended for one party over another, effectively by who’s controlling the election, that creates a threat.”

Bobb is a former Trump attorney who was indicted earlier this year in Arizona in connection to the campaign’s efforts to overturn the results of the 2020 election. She pleaded not guilty.

Roughly 20 states plus Washington, D.C., accept and count mail-in ballots they receive after Election Day if they are postmarked on or before Election Day. And there’s no evidence that those states are more likely to have fraudulent elections because of their return window.

“Fringe lawsuit”

Kevin Munoz, a senior spokesperson with the Biden campaign, said these legal challenges are political.

“What we know is that Donald Trump and Republicans are starting earlier than ever to sow distrust in our democracy and attack the right to vote,” he said. “And so when we look at Nevada specifically, this is a fringe lawsuit led by the election denier in chief, Donald Trump, who did the same thing in 2020.”

Munoz said the practice of counting postmarked ballots that arrive after Election Day is common sense and has a long history in the U.S.

“States have permitted the counting of ballots received after Election Day for over a century in Pennsylvania and New Jersey,” he said. “That practice, for example, it dates back to 1813 and 1815. So, no, this is not new.”

But these legal challenges are new.

Bobb said the reason the RNC is newly focused on late-arriving ballots is because laws around mail ballots have changed a lot in the last few years — including in Nevada.

“I can’t speak to what prior RNC leadership has done before I got here or why they did or didn’t do something,” she said. “But I would say when it comes to mail-in ballots and dates received and dates processed, all of that, I would say COVID was a game changer.”

So far the RNC and others have filed ballot return challenges in states including Illinois, Mississippi and North Dakota. The case in North Dakota was thrown out by a court, but others continue to move through the courts.

Part of a nationwide GOP effort

Sam Paisley, national press secretary with the Democratic Legislative Campaign Committee, said this is part of a larger effort to shorten the windows that voters can return their mail ballots.

She said her group has tracked at least 47 bills across 18 states in the 2023 and 2024 legislative sessions that would shorten ballot return windows.

“At the end of the day, it stifles democratic participation,” Paisley said. “The deadlines seem to be ever changing and Republicans are intentionally causing that kind of confusion for voters.”

Paisley said Republicans have an absentee ballot problem they’ve created. She said their voters are wary of voting by mail and it could be a political liability for them — which is why they’re trying to shorten the window in which people can return their ballot.

“They obviously have made the calculation that it’s for their political benefit,” she said. “But I think it is just part of a very long history of voter suppression.”

While Republicans led by Trump have disparaged mail voting, they are now trying to change their tune. On Tuesday, the Trump campaign and the RNC launched a “Swamp The Vote” initiative “to promote the use of absentee and mail ballots and early in-person voting.”

Some veterans groups filed a legal brief in Nevada arguing that not counting ballots that arrive after Election Day could have a disproportionate impact on military voters.

“If Plaintiffs are successful, the voters most likely to be disenfranchised are active and former members of the Armed Services and their families, as well as older and disabled voters, all of whom rely heavily on mail ballots to exercise their right to vote,” the groups told the court.

But the RNC said cutting off mail ballot returns at Election Day won’t necessarily affect military voters.

“I have voted overseas as a military member stationed overseas and it was all done via email,” Bobb said. “So, it depends on the state and it depends on the location of how they’re handling … but certainly we want to make sure that every military member and overseas civilian has the right to vote and can do so effectively.”

Experts have expressed concern about the security of voting over the internet.

In Nevada, Durmick said not allowing late-arriving mail ballots could impact all kinds of voters.

“If we have somebody that’s working multiple jobs and has multiple children and, you know, this is just not something that is 100% top of their mind and they forget about their vote-by-mail ballot and they are able to put it in a mail on Election Day,” they said. “That really does increase their access. But really, I really do feel that it could happen to anybody.”