A Democratic senator said Thursday he is launching an investigation into changes at the U.S. Postal Service that are causing delays in mail deliveries across the country just as big volume increases are expected for mail-in election voting.

A plan imposed by Louis DeJoy, a Republican fundraiser who took over the top job at the Postal Service in June, eliminates overtime for hundreds of thousands of postal workers and orders that mail be kept until the next day if distribution centers are running late.

Michigan Sen. Gary Peters, the top Democrat on the Homeland Security and Governmental Affairs Committee, said DeJoy, an ally and donor of President Donald Trump, has failed to provide answers about service delays “that are preventing Americans from receiving critical mail on time, including prescription drugs, business mail and mail-in ballots.″

Peters is asking the public to provide their stories about delays or other problems with deliveries.

The Senate inquiry comes as lawmakers increasingly focus on the Postal Service, which is reeling from mail delays and financial problems at a time when record numbers of mail ballots are expected in the November presidential election because of the coronavirus pandemic.

Trump, a vocal critic of the Postal Service, contended Wednesday that “the Post Office doesn’t have enough time” to handle a significant increase in mail-in ballots. He said, “I mean you’re talking about millions of votes. … It’s a catastrophe waiting to happen.″

DeJoy met with Senate Democratic Leader Chuck Schumer and House Speaker Nancy Pelosi Wednesday in what Schumer called “a heated discussion.″

Democrats told DeJoy that “elections are sacred” and urged him not to impose cutbacks “at a time when all ballots count,″ Schumer said. “You can’t say, ‘Oh, we’ll get 94%.’ It’s insufficient. We are demanding that the regulations they put in place, which cut employment and cut overtime, be rescinded, particularly because of COVID and because of the elections.″

The House Oversight Committee has called DeJoy to testify at a hearing next month.

Sen. Peters said in a statement, “For 245 years, the Postal Service has worked to provide reliable, consistent and on-time delivery that keeps Americans connected no matter where they live – especially in rural areas.”

“Unfortunately, in recent weeks, I’ve heard firsthand from constituents, postal workers and local officials in Michigan who have encountered problems with the timely and dependable service they count on to conduct business, get prescription medications and critical supplies and even exercise their right to vote.″

Democrats are calling for the Postal Service to rescind the restrictions on overtime and other operational changes, and they have pushed for $10 billion for the Postal Service in talks with Republicans on a huge COVID-19 response bill. The figure is down from a $25 billion plan in a House-passed coronavirus measure. Key Republicans whose rural constituents are especially reliant on the post office support the idea.

David Partenheimer, a spokesman for the Postal Service, declined to comment on DeJoy’s meeting with Democrats. But he said the agency is using all available resources to “match the workload created by the impacts of the ongoing coronavirus pandemic.″ The Postal Service has “a liberal leave policy” and is aggressively trying to hire qualified candidates to replace tens of thousands of workers who have gotten sick or opted not to work because of the pandemic, he said.

“We appreciate the patience of our customers and the efforts of employees as conditions change on a day-to-day basis,″ he said.

Partenheimer disputed reports that the Postal Service is slowing down election mail or any other mail. “We continue to employ a robust and proven process to ensure proper handling of all election mail consistent with our standards,″ he said.

(AP)