s are conventionally ranked by the length of their tenure in the Senate. The senator in each U.S. state with the longer time in office is known as the senior senator; the other is the junior senator. This convention has no official standing, though seniority confers several benefits, including preference in the choice of committee assignments and physical offices. When senators have been in office for the same length of time, a number of tiebreakers, including previous offices held, are used to determine seniority.
Benefits of seniority
The United States Constitution does not mandate differences in rights or power, but Senate rules give more power to senators with more seniority. Generally, senior senators will have more power, especially within their own caucuses. In addition, by custom, senior senators from the president's party control federal patronage appointments in their states. There are several benefits, including the following:
Senators are given preferential treatment in choosing committee assignments based on seniority. Seniority on a committee is based on length of time serving on that committee, which means a senator may rank above another in committee seniority but be more junior in the full Senate. Although the committee chairmanship is an elected position, it is traditionally given to the most senior senator of the majority party serving on the committee, and not already holding a conflicting position such as chairmanship of another committee. The ranking member of a committee is elected in the same way.
Greater seniority enables a senator to choose a desk closer to the front of the Senate Chamber.
Senators with higher seniority may choose to move into better office space as those offices are vacated.
The beginning of an appointment does not necessarily coincide with the date the Senate convenes or when the new senator is sworn in. In the case of senators first elected in a general election for the upcoming Congress, their terms begin on the first day of the new Congress. Since 1935, that means January 3 of odd-numbered years. The seniority date for an appointed senator is usually the date of the appointment, although the actual term does not begin until they take the oath of office. An incoming senator who holds another office, including membership in the U.S. House of Representatives, must resign from that office before becoming a senator.
Determining length of seniority
A senator's seniority is primarily determined by length of continuous service; for example, a senator who has served for 12 years is more senior than one who has served for 10 years. Because several new senators usually join at the beginning of a new Congress, seniority is determined by prior federal or state government service and, if necessary, the amount of time spent in the tiebreaking office. These tiebreakers in order are:
Population of state based on the most recent census when the senator took office
Alphabetical by last name
When more than one senator has served in the same previous role, length of time in that prior office is used to break the tie. For instance, Ben Cardin, Bernie Sanders, Sherrod Brown, Bob Casey, Amy Klobuchar, Sheldon Whitehouse and Jon Tester took office on January 3, 2007, and the first three senators mentioned had previously served in the House of Representatives. Cardin, having served 20 years, is more senior than Sanders, who served 16 years, who in turn is more senior than Brown, who served 14 years. Casey, Klobuchar, Whitehouse, and Tester rank in that order because as of the 2000 census, Pennsylvania, Minnesota, Rhode Island, and Montana had populations that ranked in that order, so Tester is ranked 33rd in seniority when the 116th United States Congress convened.
Only relevant factors are listed below. For senators whose seniority is based on their state's respective population, the state population ranking is given as determined by the relevant United States Census current at the time that they began service.
