SPRINGFIELD — Two 5th District Appellate Justices — Republican David K. Overstreet and Democrat Judy L. Cates — will face off later this year to fill the downstate seat on the Illinois Supreme Court currently held by Justice Lloyd A. Karmeier.

Cates ran unopposed in the primary, locking-down the Democratic nomination.

Overstreet secured a decisive victory over 5th District Appellate Justice John B. Barberis Jr., earning 76.5% of the vote, according to unofficial election results. Barberis obtained 23.5% of the vote.

“As your next Supreme Court Justice, I pledge to serve as a strict Constitutional conservative,” Overstreet said in a statement released Tuesday night. “I will stand up for all of our shared constitutional rights and I will not legislate from the bench.”

In an interview on Wednesday, Overstreet thanked his family and friends, as well as those who voted for him in the primary.

“I look forward to campaigning in the general election when it’s appropriate,” he said.

Barberis, who conceded late Tuesday night on social media, said voters “need to get behind Justice Overstreet 100%” in the November election.

The GOP duel pitted self-described “true conservative” Barberis against advertised “constitutional conservative” Overstreet in a campaign over endorsements and bar association ratings.

Barberis, 52, earned the support of Republican members on the Madison County Board and the Madison County Republican Party. The Illinois State Bar Association rated him “not recommended.”

Overstreet, who the ISBA rated “highly recommended,” had backing from the Illinois State Rifle Association, the Illinois Fraternal Order of Police and Citizens for Life, an anti-abortion organization. He also received nods from a handful of former and current Republican state legislators and from Mary Karmeier — the wife of Lloyd A. Karmeier.

Lloyd Karmeier appointed Overstreet in 2007 to an open 2nd Judicial District circuit court seat and reassigned him to the appellate court in 2017. Overstreet ran the following year for an open seat on the same court and won.

Overstreet, 54, has described Karmeier as his role model.

Overstreet and Cates will run against one another in the November general election. Barberis will remain on the appellate bench. His term expires in 2026.

Cates, 67, was rated “highly recommended” by the ISBA. She was elected to the 5th District Appellate Court in 2012. Before that, she spent about 30 years in private practice.

She didn’t respond to a request for comment.