Seniority in the United States Senate
United States senators 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. Per traditions, the longest serving senator of the majority party is named president pro tempore of the Senate, the second-highest office in the Senate and the third in the line of succession to the presidency of the United States.[1]
For seniority list of all United States senators who ever served in the current Congress, see List of United States senators in the 118th Congress.
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: