After being elected, a United States Senator serves a term of 6 years. Senators are allowed to run for office as many times as they wish.
Senators are representatives of the various states that make up the United States of America. Each state elects two senators, making a total of 100. The total number of senators can only change if a state is added to the union.
To qualify as a senatorial candidate, an individual must be a U.S. citizen for a minimum of 9 years. The candidate must be at least 30 years of age, and a resident of the state he or she wishes to represent.