Pennsylvania’s Democratic Party sued the Erie County Board of Elections on Wednesday over “numerous issues related to the mail-in voting process.”

The lawsuit says that the U.S. Postal Service is unable to account for about 1,800 ballots and 300 duplicate ballots were incorrectly sent out to the county voters.

“Upon information and belief, it appears that 10,000 to 20,000 voters who requested mail-in ballots have not received or submitted such ballots,” the complaint read.

The lawsuit argues that these irregularities have the potential to disenfranchise thousands of voters.

The party is asking the court to order the county to release the names of the voters who may be affected and prepare provisional ballots, among other forms of relief.

A lawyer representing the state’s Democratic Party did not immediately respond to a request for comment.

According to the Philadelphia Inquirer, this is the first lawsuit filed by the Democratic Party in Pennsylvania ahead of the Nov. 5 Election Day.

According to the outlet, Erie is a bellwether county, “and residents know the familiar refrain: ‘where Erie goes, so goes Pennsylvania.’”

A spokesperson from Erie County did not immediately respond to a request for comment.

The lawsuit was filed on the same day that the Trump campaign won a separate lawsuit filed in Bucks County, Pennsylvania, over the handling of mail-in ballots.

The Trump campaign argued elections officials were turning voters away from long lines who tried to obtain their mail in ballots by Tuesday’s deadline. The judge ordered voters in that county to have until Nov. 1 to obtain their mail-in ballot.