(AP) – Roughly six weeks before the first midterm ballots are mailed out, the U.S. Postal Service is emerging as a pivotal player in an election season that will determine control of Congress.

President Donald Trump is seeking greater control over mail balloting through an executive order while a change to how the agency processes mail is leading to criticism that it’s failing to deliver ballots on time.

Democratic officials have raised concerns over the past week about how quickly the Postal Service will process ballots after tens of thousands of them in California and hundreds in Wisconsin arrived at local election offices too late to be counted in elections earlier this year. The top election offices in Kansas and Michigan are urging voters who want to cast their ballots early to avoid the mail and instead drop them off in person.

The Postal Service replied to those concerns Tuesday by saying it remains “committed to fulfilling our role in the electoral process.”

“We provide a secure, efficient, and effective way for citizens to participate when policymakers decide to use mail as part of their elections,” it said in a statement.

Trump’s order puts more focus on mail ballots
The Postal Service faced similar questions about mail delivery in 2024, but the scrutiny this year is heightened because of an executive order Trump issued in March that seeks to create a national voter list to guide the Postal Service in deciding who gets a mail ballot.

The order has sparked multiple lawsuits and federal court orders, leading to a case now before the U.S. Supreme Court in which the administration is asking the justices to allow it to impose its restrictions on mail balloting.

Trump has lied for years about voter fraud to try to explain away his loss to Democrat Joe Biden in 2020, and mail balloting is a favorite target, even though he has used the method himself. During a recent stop in Michigan, he falsely characterized mail balloting as “inherently corrupt” and added, “Hopefully there will be no mail-in ballots.”

A 2025 report from the research group Brookings identified about four cases of fraud for every 10 million mail ballots cast.

Despite Trump’s attacks, the method remains popular with voters of both major parties. In 2024, nearly 30% of U.S. voters cast their ballots by mail, according to federal data. In Michigan, where competitive U.S. House and Senate races could help determine the balance of power in Congress, the state said it has sent out more than 2 million absentee ballots for the state’s Aug. 4 primary.

“We want to keep vote by mail. We want to protect it. We want to expand it,” said Jonathan Smith, president of the 200,000-member American Postal Workers Union, which launched a campaign in April promoting it and is opposed to turning the Postal Service into an election administrator. “Why? Because it works.”

Legal battles intensify over Trump’s order
The Postal Service proposed a rule in June in line with Trump’s executive order that would create a national list of eligible voters, based on databases kept by other federal agencies. Only those on the list would be eligible to receive mail ballots.

Democratic officials in nearly two dozen states filed a federal lawsuit in Massachusetts. A federal judge there blocked Trump’s order last month, and an appeals court upheld that ruling, prompting Trump’s appeal to the Supreme Court. But the appeals court for the District of Columbia refused Tuesday to block the order in a separate case, calling a legal challenge premature.

Democratic senators and governors have written to the Postal Service urging it to abandon efforts to implement Trump’s order.

“Donald Trump has shown he’ll stop at nothing to meddle in our upcoming elections,” Wisconsin Sen. Tammy Baldwin said in a statement to The Associated Press. “At best, this new push will exacerbate already severe delays for mail-in voters and at worst, it will stop eligible Americans from casting their ballots.”

Sophia Lin Lakin, ACLU Voting Rights Project director, said she doesn’t believe the Postal Service has begun implementing anything related to Trump’s executive order while the legal challenges are playing out. But Smith, of the postal workers union, told the AP on Tuesday that USPS information technology staffers who are union members are working on a planned portal for the list of eligible voters “behind the scenes.”

The Postal Service declined to respond to Smith’s statements and said it could not comment about whether it’s moving forward with work related to Trump’s order because of the litigation.

The postal workers’ union opposes the plan for a portal, a national list of eligible voters and using that list to determine who can receive a mail ballot. Smith said it shouldn’t be postal workers’ responsibility “to decide who can vote and who can’t vote.”

A plan to consolidate mail processing centers upsets officials
The Postal Service has been under financial stress for years and has been consolidating mail processing into fewer regional centers. Mail travels an average of 139 miles (224 kilometers) to reach one and sometimes 500 miles (805 kilometers), according to a recent Brookings report.

In January, a group of mostly Democratic senators said it was concerned about a decision to end twice-daily mail dispatches from local post offices to regional processing centers. The result is that mail arriving after the only daily dispatch would go out the next day.

California officials said the change was a factor in the state rejecting more than 148,000 ballots from its June primary, with 63% of them arriving too late despite a seven-day grace period. Officials worried that some ballots were postmarked at processing facilities the day after they were dropped off at a post office, possibly invalidating them. Wisconsin officials also said hundreds of ballots from an election in April arrived late.

The Postal Service said postmarks generally are being applied with automated equipment at processing centers, “in the same manner and to the same extent as before.” It said someone who wants to make sure their ballot envelope gets a timely postmark can get a free one applied by a postal worker.

A report on the 2024 election by the USPS Office of Inspector General said the Postal Service handled more than 59 million pieces of ballot mail from Sept. 1 to Nov. 15 that year and that 97.3% arrived on time.

Some state election officials advise voters to avoid the mail
The Michigan secretary of state’s office is advising voters to hand-deliver ballots to their local clerk’s office or a drop box.

“We’ve seen these issues over a number of election cycles now — they’re always concerning, and that’s why we’ve put out that guidance,” said Deputy Secretary of State Aghogho Edevbie.

The Postal Service said its Michigan centers are not seeing processing delays.

In Kansas, concerns about late ballot deliveries in the state’s 2024 primary election prompted a quip on the social platform X from Secretary of State Scott Schwab, a Republican: “The Pony Express is more efficient at this point.” Asked his view now, spokesperson Whitney Tempel said Schwab still believes “keeping your ballot out of the hands of the federal government is best.”

Jamie Shew, a Democrat elected to oversee elections in Douglas County, home to the main University of Kansas campus, said his office is trying to change voters’ perceptions.

“I think voters are used to, you can drop it off on Friday and we’re going to receive it by Election Day,” Shew said Tuesday. “That’s just not the reality.”

California’s state budget includes $10 million for social media campaigns and other efforts to discourage last-minute ballot mailings.

And the Postal Service said it hasn’t changed its own longstanding advice for voters: They should get their ballots in the mail at least a week before their state’s deadline for receiving them.