Seniority in the United States Senate

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:

• Traditionally, the most senior member of the majority party is named president pro tempore of the Senate.
• 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 (called the vice-chairman in some select committees) 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.
• Seniority determines the ranking in the United States order of precedence although other factors, such as being a former president or First Lady, can place an individual higher in the order of precedence.

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.

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:[1]

1. Former senator
2. Former vice president
3. Former House member
4. Former Cabinet secretary
5. Former state governor
6. Population of state based on the most recent census when the senator took office
7. Alphabetical by last name (in case two senators came from the same state on the same day and have identical credentials)

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.[2][3][4]

  Republican (53)       Democratic (45)       Independent (2)

• Current members of the United States Senate
• Seniority in the United States House of Representatives
• List of members of the United States Congress by longevity of service
• List of longest-living United States senators