FACT WIKI · Concept
United States Senate elections
United States Senate elections
Regular United States Senate elections renew roughly one-third of the chamber's 100 seats every two years. Senators serve six-year terms, and the seats are divided into three election classes so that the entire chamber does not face election at once.
Roles and functions
Staggered elections make the Senate a continuing body: roughly two-thirds of its members carry over into the next Congress, apart from vacancies such as those caused by death or resignation. Unlike the House, the Senate is therefore not constituted anew after every election cycle.
How it works
Each state's two Senate seats belong to different election classes. Their regular terms therefore end in different years, rather than both seats routinely coming up for election together.
History and changes
Article I, Section 3, Clause 2 of the Constitution established the three Senate classes. In May 1789, the Senate of the First Congress carried out the original division by drawing lots.
Scope and limitations
The class schedule governs regular elections for fixed terms. A special election to fill a vacancy, such as one caused by a senator's resignation or death, may take place in a different year regardless of the seat's class.
Background and related concepts
All House members face election every two years, allowing the House's membership and agenda to change substantially in a single cycle. Constitutional commentary describes the Senate's six-year staggered terms as a source of institutional stability that can counterbalance those changes.
References
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