On October 14, a U.S. Senate debate was held in West Virginia. Participants included three of the four candidates on the ballot: Republican John Raese , Mountain Party nominee Jesse Johnson, and Constitution Party nominee Jeff Becker. See this story. The Democratic nominee, Joe Manchin, did not attend, but he did provide written answers to the debate questions.
All four candidates will debate on October 18; see this story. That debate will be televised and will be the first televised debate in West Virginia that includes a minor party debating major party opponents. Thanks to the commenters for improving the accuracy of this post.