ATLANTA -- A Federal judge ordered the state of Georgia to extend 6th district voter registration to May 21.

Civil rights lawyers filed a federal complaint asserting that Georgia's voter registration laws violate federal laws. Thursday afternoon, a federal court judge agreed, saying the state's law limiting registration does not apply to special elections.

The complaint was filed in the United States District Court for the Northern District of Georgia by multiple civil rights organizations, including the Georgia NAACP. It challenges a Georgia law that cuts off voter registration for federal runoff elections two months earlier than guaranteed under federal law.

Under Section 8 of the National Voter Registration Act, states must ensure that a person can vote in an election for a federal office "if he or she registers to vote at least 30 days before that election," including runoff elections.

Georgia law as it is now allows a person to vote in the election if they register at least 30 days before that election, however, it does not allow a voter to cast a ballot in the runoff if they had not registered in time for the general election. The complaint alleges that violates federal law.

In the example of Georgia's recent special election for the Georgia's 6th District race, voters must have registered to vote by March 20 in order to be eligible for this past week's April 18 election. However, under Georgia law, unless voters were registered by that cutoff date, they cannot cast a ballot in June's runoff.

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Ezra Rosenberg, one of the lawyers affiliated with the suit, called it a necessary step in order to provide the people of Georgia the "full protections of federal law."

“Cutting off the registration period as Georgia does before a runoff election makes no sense, and deprives thousands of Georgians of the right to exercise their franchise,” Rosenberg said when the lawsuit was filed.

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When the lawsuit was filed, the Secretary of State's office said the lawsuit was "nothing more than a political attack against Secretary Kemp," pointing to the fact that the law had been in place since former Secretary Cathy Cox was in office.

According to Kemp's office, the Georgia Constitution and Georgia law establish that a runoff is a continuation of an "underlying" election and a voter must have been registered for that election to be qualified to vote in the runoff. Further, Kemp's office argues, "changing the registration deadline this close to the election runoff would put the integrity of the special election runoff at great risk."

In the statement, the Secretary of State's office said the election system is setup such that the runoff election must be connected to the underlying election. Any changes this late in the process would cause complications for absentee ballots and more, Kemp's office argued.

"The risk of harm that could be caused from attempting to put in place a brand new procedure outweighs any potential gain from having a new registration deadline, even more so given that the 6th Congressional District already has the highest registration rate of Georgia’s Congressional Districts," the statement concludes.

Thursday, they lost that argument when the judge agreed to extend the registration deadline to May 21.

In response to the judge's decision, 6th District candidate Jon Ossoff issued a statement in support of the ruling.

"Voting rights are constitutional rights," his campaign said. "I encourage all eligible voters to ensure that they are registered and make their voices heard on June 20th and in all elections, regardless of their party or political persuasion.”

Photos | Election day in the 6th district