The seniority in the United States Senate is based upon a series of ranked factors; only resorting to the next factor when tied.1
Senior senator and junior senator are terms commonly used in the media to describe United States senators. Each state sends two senators to serve in the Senate; the longer (continuously) serving of the two is by convention referred to as the senior senator, and the other is referred to as the junior senator. If both are elected at the same time (e.g., one in a regular election and the other simultaneously to fill the seat of a senator who resigned), the one who is sworn in first is senior.
There is no mandated difference in rights or power, although Senate rules give more power to senators with more seniority. Generally, senior senators will have more power, though being a member of the majority party is more advantageous than being senior. In addition, by custom the senior senators from the president's party control federal patronage appointments in their states. Thus being the junior senator is disadvantageous if the senior one is from the same party.
Some of the perquisites of seniority offered by the U.S. Senate:
Senators are given preferential treatment for committee assignments based on seniority. 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. Ranking member (called vice-chairman in some select committees) of a committee is the most senior member of the minority party thereon.
Greater seniority enables a senator to choose a desk closer to the front of the Senate Chamber.
Traditionally, seniority brings with it greater clout. As a result, it is generally difficult for the more junior members of both houses of Congress to have a significant impact on policy.
Only relevant factors are listed. For instance, Byrd's time with the House of Representatives no longer has any bearing on his seniority, so it is not listed.
Amount of consecutive time serving as U.S. senator
Previous U.S. senator (non-consecutive)
Length of time serving as a senator in previous non-consecutive terms
Population of state based on the most recent census when the senator took office
Alphabetical by last name (in the rare instance that two senators came from the same state on the same day and have identical credentials)
For senators whose seniority is based on their states' respective populations, the state population ranking, as determined by the relevant United States Census,2345 is given.
^ abcde Announced retirement after 2008 election (not running for re-election).
^ Biden has been elected vice president of the United States and will resign his Senate seat on or before January 20, 2009.
^ Bingaman is currently the most senior junior senator. New Mexico's senior senator is Pete Domenici who is 5th in seniority. In January 2009, Bingaman will become the state's senior senator, at which time Senator John Kerry of Massachusetts will become the most senior junior senator.
^Joe Lieberman won re-election as a third party candidate in 2006 and caucuses with the Democratic Party. However, he has chosen to refer to himself as an "Independent Democrat." Despite the party change, Lieberman retains his seniority since there is no break in his Senate service.
^ Frank Lautenberg served a previous term as U.S. Senator from New Jersey from January 1983 to January 2001, but under the rules, does not retain seniority from that prior service. Lautenberg has sought restoration of his seniority based on his prior service, but has not received it. - HillNews.com
^ Phil Gramm resigned early, effective November 30, 2002, so that Cornyn could take senate office on December 2, 2002, and move into Gramm's office suite in order to begin organizing his staff. Cornyn did not, however, gain seniority, owing to a 1980 Rules Committee policy that no longer gave seniority to senators who entered Congress early for the purpose of gaining advantageous office space.
^Norm Coleman is currently the most junior Senior Senator. Minnesota's Junior Senator is Amy Klobuchar who is 96th in seniority.
^ Senator Webb served as Secretary of the Navy; however, that has not been a Cabinet-level position since 1947 and therefore does not affect his Seniority.
^ This seat was resigned by President-elect Barack Obama effective November 16, 2008. [1]