Voters who were never mailed their absentee ballots filed a lawsuit Sunday asking a judge to require Cobb County to send ballots by overnight mail and extend the state’s deadline to return them.

The lawsuit comes after Cobb election officials acknowledged Friday that they failed to mail absentee ballots to 1,036 voters who had requested them.

Many of those voters, especially those who live outside the county, are now at risk of being unable to participate as Election Day approaches on Tuesday, according to the suit.

“Hundreds of eligible Cobb County voters did everything right and yet find themselves on the brink of total disenfranchisement because they were never mailed their absentee ballots, as is required under Georgia law,” said Jonathan Topaz, an attorney for the American Civil Liberties Union’s Voting Rights Project.

Absentee ballots are supposed to be mailed within three days after election officials receive ballot requests from voters during the three weeks before Election Day, according to state law.

But election workers neglected to upload absentee information to a ballot mailing machine on Oct. 13 and Oct. 22, said Cobb Election Director Janine Eveler. She acknowledged the error Friday and said election workers made a “critical error.”

The lawsuit was filed in Superior Court by four voters living out of state who weren’t mailed absentee ballots and the Cobb County Democracy Center, a voter education organization.

Without relief from the courts, it’s unlikely that voters will be able to return their ballots in time to be counted, the lawsuit said. Under Georgia law, absentee ballots must be received at election offices by the time polls close on Tuesday, with a later deadline of Nov. 14 for military and overseas voters.

The lawsuit asks a judge to allow ballots to be returned by the later deadline for affected Cobb County voters.

“Cobb County residents should not be stripped of their vote and their voice in government due to their ballots being mailed out late,” said Poy Winichakul, an attorney for the Southern Poverty Law Center.

Besides Cobb’s elections office, the ACLU of Georgia also blamed Georgia’s voting law passed last year, which shortened the period to request and return absentee ballots.

Before the law, voters could request absentee ballots 180 days before an election and the county could being mailing them 49 days beforehand. Under the new law, ballots can only be requested within 78 days of an election, and they can’t be mailed until 29 days before Election Day.

Voters who didn’t receive their ballots can instead vote in-person on Election Day, and the election workers are attempting to contact voters by email or phone.

Of the 1,036 voters who weren’t sent ballots, Cobb officials said 271 of them already canceled their absentee ballots and instead voted in-person during early voting, which ended Friday.