Dennis spent many hours of his youth helping his father in his milk truck. He graduated from White Bear Lake High School. Over his teenage years he won multiple national championships in BMX racing.
At North Dakota State University, Dennis served as President of Phi Beta Lambda for the entire state of North Dakota and President of Toastmasters in Fargo.
Post-graduation Dennis worked for AT&T in a variety of roles, including three years at the worldwide headquarters in New Jersey.