This story is part of Elections 2020, CNET’s coverage of the run-up to voting in November.

More than 80 million voters are expected to cast their ballots by mail this fall so that they can avoid polling places and the risk of COVID-19.

But instead of ramping up capacity to handle what could be double the number of mail-in ballots cast over the last presidential election, the US Postal Service took a series of steps this summer that could dramatically cut back its ability to handle the unprecedented number of ballots it will receive. US Postmaster General Louis DeJoy now intends to pause his planned changes, which include closures of mail processing machines, until after the Nov. 3 presidential election, amid a bipartisan outcry.

Here’s what we know about mail-in and absentee voting and how you can make sure your vote counts this fall.

Why is this a big deal?

The reductions planned by DeJoy, who was appointed by President Donald Trump in June, includes taking offline 671 of its high-capacity letter sorting machines, removing collection boxes in Western states, limiting overtime and cutting back post office hours.

The Postal Service has advised states it can’t guarantee ballots will reach voters before the election. In letters sent to 46 states and the District of Columbia, the Postal Service warned “there is a significant risk that the voter will not have sufficient time to complete and mail the completed ballot … in time for it to arrive by the state’s return deadline.”

These moves, which the post office had said it was taking to “run more efficiently,” come as Trump makes contradictory remarks about the post office. He has threatened to cut off funding for the service and followed shortly after by tweeting that he wants to “SAVE THE POST OFFICE!”

The result of all the planned changes ahead of the election, according to election lawyer Marc Elias, is that the Postal Service wouldn’t be prepared to handle the surge of mail-in ballots in November. “The Trump administration has turned to weakening the United States Postal Service in a cynical effort to keep people from voting,” Elias wrote last week.

Why is the US post office at the center of debate?

The US Postal Service, which is established under the US Constitution, has been in financial straits for years. It lost $69 billion from 2007 to 2018. The coronavirus pandemic has put additional strain on the service, curbing the volume of big money-makers — first-class and marketing mail — because people are at home. The pandemic also turned funding for the service into a bargaining chip, with the White House and Congress wrestling with how — and at sometimes if — they should fund the service.

In addition to operational changes, DeJoy has recast management of the USPS by removing or reassigning more two dozen top postal officials. Critics called the move the “Friday night massacre.”

The changes are causing significant mail delays, postal workers say. But what caught the attention of Democratic lawmakers was the warning by the postal service that it couldn’t guarantee it could handle the flood of absentee ballots in the November election.

House Speaker Nancy Pelosi and fellow House Democrats said the changes constitute “a grave threat to the integrity of the election and to our very democracy.”

Pelosi called House members back from recess to vote on a USPS rescue bill and to conduct a hearing with DeJoy about his actions.

What does the USPS have to do with mail-in ballot fraud?

Trump has claimed without proof for weeks that universal mail-in voting will lead to wide-spread voting fraud.

Every state lets voters cast a ballot by mail, ranging from absentee voting, which allows voters to request ballots by mail because they will be unable to vote in person, to what Trump calls “universal mail-in voting,” election officials automatically sending vote-by mail ballots to each person on the registration rolls.

There is no evidence, however, to support Trump’s claims. “Mail ballot fraud is incredibly rare,” reported the Brennan Center, a nonpartisan policy institute. “None of the five states that hold their elections primarily by mail has had any voter fraud scandals since making that change,” the center reported.

Members of Trump’s own party disagree with his assertions. “I don’t know of any evidence that voting by mail would increase voter fraud,” Sen. Mitt Romney said during an interview this month with Sutherland Institute.

How can you make sure your vote counts?

If you are concerned that your mail-in vote may not count this fall but want to avoid election-day crowds, elections attorney Elias recommends three ways to ensure your ballot is counted.

Vote early in person: Forty-one states allow voters to cast their ballots up to 45 days before election day, letting them avoid crowds.

Use a ballot drop box: Many states and counties provide ballot drop boxes for voters to return mail-in ballot without having to mail it.

Drop off your ballot at an election office or polling location: Almost all states permit voters to return a delivered ballot in person at their local election office on or before election day, Elias said, and many states allow voters to drop off their signed and sealed ballots at any in-person voting location.

For more, here’s the difference between absentee and mail-in voting, how we’ll vote this fall and how Facebook is helping you find election information.