The US Postal Service (USPS) has warned that millions of mail-in votes may not arrive in time to be counted on the presidential election day, 3 November.
In letters to states across the country last month, the agency said “certain deadlines… are incongruous with the Postal Service’s delivery standards”.
Critics have blamed the new USPS head – a loyal supporter of President Donald Trump – for a slowdown in deliveries.
A record number of people are expected to vote by mail due to the pandemic.
Mr Trump has repeatedly said that mail-in ballots will give a boost to his rival Democrat Joe Biden, and lead to voting fraud. Experts say the mail-in voting system – which is used by the American military and by Mr Trump himself – is safe from tampering.
The service is in financial trouble and new Postmaster General Louis DeJoy – a major Republican donor – has introduced changes such as clamping down on overtime and halting late delivery trips.
Critics say the overhauls have led to an increase in mail wait times.
On Thursday, Mr Trump said he was blocking additional funding for the USPS to help with election issues because he opposed mail-in voting.
The top two Democrats in Congress, Nancy Pelosi and Chuck Schumer, weighed in on the debate on Friday, calling on Mr DeJoy to “quickly reverse his operational changes that have led to delays and service reductions for too many Americans and threaten to undermine our democracy”.
“House and Senate Democrats call on the President to immediately cease his assault on the Postal Service, make clear that he will allow the 2020 election to proceed without his sabotage tactics,” they added in a statement.
What did the USPS say?
The USPS sent letters to states across the US in July, warning that it could not guarantee that all votes cast by mail would arrive on time to be counted.
In a letter sent to Pennsylvania’s secretary of state, the USPS said mail-in ballots requested one week before the 3 November election – which the state allows under its election laws – may not reach their destination on time because the state’s deadlines are too tight for its “delivery standards”.
USPS General Counsel Thomas Marshall said a “mismatch” between Pennsylvania’s laws and the delivery capabilities of the mail system “creates a risk that ballots requested near the deadline under state law will not be returned by mail in time to be counted under your laws as we understand them”.
The letter was made public on Thursday as Secretary of State Kathy Boockvar asked the state’s supreme court to allow ballots to be counted as long as they were received up to three days after the election. Currently, votes are discarded if they are received after election day.
Pennsylvania is a battleground state, which Mr Trump won by less than 1% in the 2016 election.
Other battleground states, including Florida and Michigan, also received letters, according to US media reports.
The Democratic governor in Pennsylvania’s neighbouring New Jersey announced on Friday that the state would pre-emptively send ballots to every registered voter in the state. The process of sending out ballots is known as universal mail-in voting, and has been adopted in nine other US states.