John Cauthorn was born in Audrain County on December 11, 1946. His father was a Farmer. His mother taught grade school and special education, before serving 10 years as the Principal of McMillan Elementary School.

John married Teresa Kueckelhan on May 29th, 1988. Teresa is an Area Sales Manager of Livestock Products for MFA Incorporated. John has three children, Elizabeth, Kaitlyn and Andrew.

John began his education in a one-room country schoolhouse. After four years his parents paid tuition for him to attend Mexico Public Schools. He graduated from Mexico High School in 1965, where he enjoyed 4-H and FFA.

John attended Missouri State Teachers College (Truman State University) in the fall of 1965. He enrolled in the National Guard in 1967, serving six-years in the 128th Field Artillery Unit, ending at a rank of Sergeant.

In the winter of 1967, John bought his first farm. Even as many farmers have been forced to consolidate or sell, John has continued to expand and grow his operation. He raises beef and pork, and grows corn.

John has been very active in his service to the farm community. He serves as an Advisory Board member for MFA Oil and MFA Incorporated. He is a member of Audrain County Farm Bureau and ASCS. He is a member of the Missouri Corn Growers Association, and Missouri Pork Producers. John is the immediate Past-President of the Missouri Cattleman's Association, after having served as Vice-President, and Secretary/Treasurer. He is a member of the National Cattlemen's Beef Association, where he serves on the Agriculture Policy Committee.

He is also involved in his local community, including the McMillan PTA. In 1999, he and his wife received the Dale Schnarre Rural Citizen Award from the Mexico Chamber of Commerce. The award is given annually for community service and farm management.

John was elected in a Special Election in January 2001 to fill the un-expired term of Lt. Governor Joe Maxwell. With his victory, the balance of power in the Missouri Senate shifted to Republican control for the first time in 52 years. In 2002, Senator Cauthorn was re-elected to serve the 18th Senatorial District winning 54% of the vote and carrying 9 of the 13 counties in the district.

In the relatively short time he has served in the Senate, Senator Cauthorn has been recognized for his outstanding leadership as a freshman legislator. In both 2001 and 2002, John has received the Missouri Corn Growers Association’s Public Servant Award. He has also received the prestigious Spirit of Enterprise Award from the Missouri Chamber of Commerce for his dedication to Missouri businesses and protecting the free enterprise system.