Each state elects two Senators to serve in the United States Congress. The Constitution mandates the equal number of Senators per state in Article 1, section 3, clause 1.
The decision to allow each state two Senators was part of the "Great Compromise" of 1787. In deciding delegation from each state, the Founding Fathers agreed to give equal representation in the Senate and to have representation determined by state population in the House of Representatives. United States Senators serve 6-year terms with no limit to the number of terms they serve. Terms are staggered so that one-third of the Senate seats are open for election every 2 years. Senators must be at least 30 years old and a citizen of the United States for at least 9 years.