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U.S. District Judge Timothy Batten ruled on Thursday that Georgia violated federal law by cutting off new voter registrations well before the June 20 runoff election in the 6th congressional district, and ordered state officials to reopen voter registration through May 21.

The suburban Atlanta district is in the spotlight due to a runoff election that many observers view as a way to measure President Trump's influence. In April, Democrat Jon Ossoff and Republican Karen Handel were the top two candidates in the special election to replace Tom Price, now the secretary of health and human services. Batten ruled that Georgia violated federal law by setting the registration deadline as March 20, 30 days before the first round of voting, and now any district resident registered by May 21 can cast their ballot in the runoff election. This applies only to the June runoff election, Batten ruled, and the state does not have to publicize this order. The lawsuit was filed by several civil rights advocacy groups.

Handel's campaign is not happy with the ruling, with spokeswoman Kate Constantini calling the lawsuit a "partisan attempt to change the rules for a nakedly partisan outcome." Ossoff told The Associated Press he is encouraging "all eligible voters to ensure that they are registered and make their voices heard on June 20 and in all elections, regardless of their party or political persuasion."