A federal judge ruled on Tuesday that a conservative group’s efforts to challenge the eligibility of hundreds of thousands of voters in the Senate runoff elections in Georgia in early 2021 did not violate the Voting Rights Act under a clause outlawing voter suppression.

In a 145-page opinion, the judge, Steve C. Jones of the United States District Court for the Northern District of Georgia, wrote that the court “maintains its prior concerns” regarding how the group, True the Vote, sought to challenge voters’ eligibility. But he said that Fair Fight, the liberal voting rights group that brought the lawsuit against True the Vote, had failed to show that the efforts were illegal.

The decision was relatively narrow, applying only to Judge Jones’s district in northern Georgia, and will do little to change the status quo: Right-wing election groups have already tried to help bring thousands of challenges to voter registrations in states across the country.

But the opinion is likely to encourage conservative activists hunting for voter fraud during the 2024 presidential election. Election officials and voting rights groups have expressed worries about these efforts, warning that an expanded campaign to challenge voters en masse could intimidate people away from the ballot box. True the Vote and similar groups, taking a cue from former President Donald J. Trump, have often spread false theories about election fraud.