NASHVILLE (AP) — A Tennessee judge on Thursday cast doubt on an attempt to allow people to participate in the state's upcoming primary election if they've had their voting rights restored after being convicted of a felony out of state.

The Campaign Legal Center had filed the lawsuit earlier this month on behalf of two residents who have both been convicted of a felony outside of Tennessee and have since had their voting rights restored in the state of their conviction.

According to the complaint, the plaintiffs have been barred from voting in the primary election because Tennessee has improperly imposed additional barriers that would clear them to submit a ballot.

During Thursday's hearing, attorneys argued for an injunction that would force the state to people who have had their voting rights restored to vote in the Aug. 6 primary and any future election.

The defendants, which include Coordinator of Elections Mark Goins, Secretary of State Tre Hargett and Attorney General Herbert Slatery, have opposed that attempt.

"There are some complex work to be done in this manner and I don't know if that can be done in time for the Aug. 6 election," Davidson County Chancellor Ellen Hobbs Lyle said.

Blair Bowie, an attorney with Campaign Legal Center, then asked if the judge could narrow her decision to whether just the two plaintiffs named in the lawsuit could vote.

However, Lyle again said that would require a lengthy review.

"I am certain that I cannot get it out tomorrow," Lyle said. "But this weekend there may be an opportunity, I'll just have to see."

Currently, Tennessee requires those who have been convicted of a felony in-state to have fully paid off their restitution and legal fees. This requirement has long sparked concern from voter advocates who argue it creates an impossible burden for those who have been convicted.

According to a 2016 report by The Sentencing Project, an estimated 421,000 Tennesseans are denied the right to vote due to felony convictions — or about 8.2% of the state's total voting population.