The North Carolina Bar Association sponsored a U.S. Senate debate held on June 26, and all three ballot-listed candidates participated. See this story. Michael Beitler, the Libertarian nominee, is apparently the first Libertarian Senate nominee in North Carolina to have debated both his or her major party opponents. He is a teacher at the University of North Carolina at Greensboro.
Every U.S. Senate election in North Carolina starting in 1992 has had three candidates on the ballot, a Democrat, a Republican, and a Libertarian.