A proposed amendment to the state constitution would require candidates for governor and lieutenant governor to run as a ticket, just as the president and vice president do. Senators debated the measure but set it aside Tuesday.
Two of Missouri's three Republican senatorial candidates are expected to meet in a debate in Branson.
U.S. Rep. Todd Akin and former state Treasurer Sarah Steelman both have committed to participate in Monday night's debate. The third candidate — St. Louis businessman John Brunner — is not planning to attend.
All three Republicans are seeking to challenge Democratic U.S. Sen. Claire McCaskill in the November elections.
Monday's debate is to be held at the Branson High School Auditorium, which has room for several hundred people.