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]

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:

Determining the beginning of a term

The beginning of an appointment does not necessarily coincide with the date the Senate convenes or when the new senator is sworn in.[2]

General elections

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. For most of American history this was March 4 of odd-numbered years, but effective from 1935 the 20th Amendment moved this to January 3 of odd-numbered years.

Run-off elections and special elections

In the case of senators elected in a run-off election occurring after the commencement of a new term, or a special election, their seniority date will be the date they are sworn in and not the first day of that Congress. A senator may be simultaneously elected to fill a term in a special election, and elected to the six-year term which begins on the upcoming January 3. Their seniority is that of someone chosen in a special election.


The seniority date for an appointed senator is usually the date of the appointment,[citation needed] 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:[2]

  1. Former senator
  2. Former Vice President of the United States
  3. Former member of the United States House of Representatives
  4. Former member of the Cabinet of the United States
  5. Former state governor
  6. Population of state based on the most recent census when the senator took office

When more than one senator had such office, its length of time is used to break the tie. For instance, Roy Blunt, Jerry Moran, Rob Portman, John Boozman, Pat Toomey, John Hoeven, Marco Rubio, Ron Johnson, Rand Paul, Richard Blumenthal and Mike Lee took office on January 3, 2011. The first five senators mentioned had served in the House of Representatives: Blunt and Moran had served for 14 years; Portman for 12; Boozman for nine; Toomey for six. Blunt outranks Moran because Missouri was ranked above Kansas by population in the 2000 census. As a former governor, Hoeven is ranked immediately after the former House members. The rest are ranked by population as of the 2000 census. These ranked from 40th to 50th in seniority when the 117th United States Congress convened.

If two senators are tied on all criteria, the one whose last name comes first alphabetically is considered the senior senator. This happened with Senators Jon Ossoff and Raphael Warnock, both of Georgia, who were sworn in on January 20, 2021. Because they were both newly elected senators from the same state, with no prior government service, no other tie-breaking criteria could be used. The Senate's official records, as well as the Democratic Caucus, thus consider Ossoff, whose name comes first alphabetically, as the senior senator, despite him being 17 years younger than Warnock.[2][3][4]

Current seniority list

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.[5][6][7]

  Republican (50)       Democratic (48)       Independent (2)

Senator Party State Seniority date Other factors Committee and leadership positions
1 1692 Patrick Leahy Democratic Vermont January 3, 1975 President pro tempore
Chair: Appropriations
2 1743 Chuck Grassley Republican Iowa January 3, 1981 President pro tempore emeritus
Ranking Member: Judiciary
3 1766 Mitch McConnell Kentucky January 3, 1985 Senate Minority Leader
4 1775 Richard Shelby Republican[b] Alabama January 3, 1987 Ranking Member: Appropriations
5 1801 Dianne Feinstein Democratic California November 4, 1992
6 1810 Patty Murray Washington January 3, 1993 Chair: HELP
7 1816 Jim Inhofe Republican Oklahoma November 16, 1994 Ranking Member: Armed Services
8 1827 Ron Wyden Democratic Oregon February 5, 1996 Chair: Finance
9 1831 Dick Durbin Illinois January 3, 1997 Former House member (14 years) Senate Majority Whip
Chair: Judiciary
10 1835 Jack Reed Rhode Island Former House member (6 years) Chair: Armed Services
11 1842 Susan Collins Republican Maine
12 1844 Chuck Schumer Democratic New York January 3, 1999 Former House member (18 years) Senate Majority Leader
13 1846 Mike Crapo Republican Idaho Former House member (6 years) Ranking Member: Finance
14 1855 Tom Carper Democratic Delaware January 3, 2001 Former House member (10 years) Chair: Environment
15 1856 Debbie Stabenow Michigan Former House member (4 years) Chair: Agriculture
16 1859 Maria Cantwell[c] Washington Former House member (2 years) Chair: Commerce
17 1867 John Cornyn Republican Texas December 2, 2002 Ranking Member: Narcotics Caucus
18 1868 Lisa Murkowski Alaska December 20, 2002[d] Ranking Member: Indian Affairs
19 1870 Lindsey Graham South Carolina January 3, 2003 Ranking Member: Budget
20 1876 Richard Burr North Carolina January 3, 2005 Former House member (10 years) Ranking Member: HELP
21 1879 John Thune South Dakota Former House member (6 years) Senate Minority Whip
22 1885 Bob Menendez Democratic New Jersey January 17, 2006[d]   Chair: Foreign Relations
23 1886 Ben Cardin Maryland January 3, 2007 Former House member (20 years) Chair: Small Business
24 1887 Bernie Sanders Independent Vermont Former House member (16 years) Chair: Budget
25 1888 Sherrod Brown Democratic Ohio Former House member (14 years) Chair: Banking
26 1890 Bob Casey Jr. Pennsylvania Pennsylvania 6th in population (2000) Chair: Aging
27 1893 Amy Klobuchar Minnesota Minnesota 21st in population (2000) Chair: Rules
28 1894 Sheldon Whitehouse Rhode Island Rhode Island 43rd in population (2000) Chair: Narcotics Caucus
29 1895 Jon Tester Montana Montana 44th in population (2000) Chair: Veterans' Affairs
30 1896 John Barrasso Republican Wyoming June 22, 2007[d] Ranking Member: Energy
31 1897 Roger Wicker Mississippi December 31, 2007[d] Ranking Member: Commerce
32 1901 Jeanne Shaheen Democratic New Hampshire January 3, 2009 Former governor (6 years)
33 1902 Mark Warner Virginia Former governor (4 years) Chair: Intelligence
34 1903 Jim Risch Republican Idaho Former governor (7 months) Ranking Member: Foreign Relations
35 1905 Jeff Merkley Democratic Oregon
36 1909 Michael Bennet Colorado January 21, 2009[d]
37 1910 Kirsten Gillibrand New York January 26, 2009[d]
38 1916 Joe Manchin West Virginia November 15, 2010 Former governor Chair: Energy
39 1917 Chris Coons Delaware Chair: Ethics
40 1919 Roy Blunt Republican Missouri January 3, 2011 Former House member (14 years);
Missouri 17th in population (2000)
Ranking Member: Rules
41 1920 Jerry Moran Kansas Former House member (14 years);
Kansas 33rd in population (2000)
Ranking Member: Veterans' Affairs
42 1921 Rob Portman Ohio Former House member (12 years) Ranking Member: Homeland Security
43 1922 John Boozman Arkansas Former House member (9 years) Ranking Member: Agriculture
44 1923 Pat Toomey Pennsylvania Former House member (6 years) Ranking Member: Banking
45 1924 John Hoeven North Dakota Former governor
46 1925 Marco Rubio Florida Florida 4th in population (2000) Vice Chair: Intelligence
47 1926 Ron Johnson Wisconsin Wisconsin 20th in population (2000)
48 1927 Rand Paul Kentucky Kentucky 25th in population (2000) Ranking Member: Small Business
49 1928 Richard Blumenthal Democratic Connecticut Connecticut 29th in population (2000)
50 1929 Mike Lee Republican Utah Utah 34th in population (2000)
51 1932 Brian Schatz Democratic Hawaii December 26, 2012[d] Chair: Indian Affairs
52 1933 Tim Scott Republican South Carolina January 2, 2013[d] Ranking Member: Aging
53 1934 Tammy Baldwin Democratic Wisconsin January 3, 2013 Former House member (14 years)
54 1937 Chris Murphy Connecticut Former House member (6 years);
Connecticut 29th in population (2010)
55 1938 Mazie Hirono Hawaii Former House member (6 years);
Hawaii 40th in population (2010)
56 1939 Martin Heinrich New Mexico Former House member (4 years)
57 1940 Angus King Independent Maine Former governor (8 years)
58 1941 Tim Kaine Democratic Virginia Former governor (4 years)
59 1942 Ted Cruz Republican Texas Texas 2nd in population (2010)
60 1943 Elizabeth Warren Democratic Massachusetts Massachusetts 14th in population (2010)
61 1944 Deb Fischer Republican Nebraska Nebraska 38th in population (2010)
62 1948 Ed Markey Democratic Massachusetts July 16, 2013
63 1949 Cory Booker New Jersey October 31, 2013
64 1951 Shelley Moore Capito Republican West Virginia January 3, 2015 Former House member (14 years) Ranking Member: Environment
65 1952 Gary Peters Democratic Michigan Former House member (6 years);
Michigan 8th in population (2010)
Chair: Homeland Security
66 1953 Bill Cassidy Republican Louisiana Former House member (6 years);
Louisiana 25th in population (2010)
67 1955 James Lankford Oklahoma Former House member (4 years) Ranking Member: Ethics
68 1956 Tom Cotton Arkansas Former House member (2 years);
Arkansas 32nd in population (2010)
69 1957 Steve Daines Montana Former House member (2 years);
Montana 44th in population (2010)
70 1958 Mike Rounds South Dakota Former governor
71 1960 Thom Tillis North Carolina North Carolina 10th in population (2010)
72 1961 Joni Ernst Iowa Iowa 30th in population (2010)
73 1962 Ben Sasse Nebraska Nebraska 38th in population (2010)
74 1963 Dan Sullivan Alaska Alaska 47th in population (2010)
75 1964 Chris Van Hollen Democratic Maryland January 3, 2017 Former House member (14 years)
76 1965 Todd Young Republican Indiana Former House member (6 years)
77 1966 Tammy Duckworth Democratic Illinois Former House member (4 years)
78 1967 Maggie Hassan New Hampshire Former governor
79 1969 John Kennedy Republican Louisiana Louisiana 25th in population (2010)
80 1970 Catherine Cortez Masto Democratic Nevada Nevada 35th in population (2010)
81 1972 Tina Smith Minnesota January 3, 2018[d]
82 1974 Cindy Hyde-Smith Republican Mississippi April 2, 2018[d]
83 1975 Marsha Blackburn Tennessee January 3, 2019 Former House member (16 years)
84 1976 Kyrsten Sinema Democratic Arizona Former House member (6 years);
Arizona 16th in population (2010)
85 1977 Kevin Cramer Republican North Dakota Former House member (6 years);
North Dakota 48th in population (2010)
86 1979 Jacky Rosen Democratic Nevada Former House member (2 years)
87 1980 Mitt Romney Republican Utah Former governor
88 1981 Mike Braun Indiana Indiana 15th in population (2010)
89 1982 Josh Hawley Missouri Missouri 18th in population (2010)
90 1983 Rick Scott Florida January 8, 2019
91 1985 Mark Kelly Democratic Arizona December 2, 2020
92 1986 Ben Ray Luján New Mexico January 3, 2021 Former House member (12 years)
93 1987 Cynthia Lummis Republican Wyoming Former House member (8 years)
94 1988 Roger Marshall Kansas Former House member (4 years)
95 1989 John Hickenlooper Democratic Colorado Former governor
96 1990 Bill Hagerty Republican Tennessee Tennessee 17th in population (2010)
97 1991 Tommy Tuberville Alabama Alabama 23rd in population (2010)
98 1992 Alex Padilla Democratic California January 18, 2021[d]
99 1993 Jon Ossoff[e] Georgia January 20, 2021 'O' 15th letter of the alphabet
100 1994 Raphael Warnock 'W' 23rd letter of the alphabet
Rank Historical
Senator Party State Seniority date Other factors Committee and leadership positions

See also


  1. ^ a b "Historical rank" refers to the senator's seniority over the entire history of the Senate since 1789, i.e. their position in the chronological ordering of all senators. This is an absolute number that does not change from one Congress to the next.
  2. ^ Richard Shelby's 1994 party change did not break his service or seniority.
  3. ^ Maria Cantwell (#16) is the Senate's most senior junior senator.
  4. ^ a b c d e f g h i j k The seniority date for an appointed senator is the date of the appointment, not necessarily the date of taking the oath of office. See Determining the beginning of a term, above.
  5. ^ Jon Ossoff (#99) is the Senate's most junior senior senator.


  1. ^ Kilgore, Ed (November 17, 2021). "Californians Move Toward Lock on Presidential Succession". Intelligencer. Retrieved February 13, 2022.
  2. ^ a b c d e "Senators of the United States 1789–present, A chronological list of senators since the First Congress in 1789" (PDF). Senate Historical Office. January 3, 2021. Retrieved January 3, 2021.
  3. ^ Bluestein, Greg. "'A new era': Ossoff, Warnock sworn into office, giving Democrats control of U.S. Senate". The Atlanta Journal-Constitution. Retrieved January 22, 2021.((cite web)): CS1 maint: url-status (link)
  4. ^ Wooten, Nick (January 20, 2021). "Will Ossoff or Warnock be Georgia's senior senator? The answer is a simple one". Ledger-Enquirer. Retrieved January 25, 2021.
  5. ^ "1991 U.S Census Report" (PDF).
  6. ^ American FactFinder, United States Census Bureau. "2000 Census State Population Rankings". Factfinder.census.gov. Archived from the original on April 3, 2009. Retrieved May 28, 2010.
  7. ^ "Resident Population Data (Text Version) – 2010 Census, by state and census region".