| | |
 |
 |
  |
 |
|
|  | Kagen, Steve | D | WI | U.S. House | 2007 – 2011 |
| | Kahele, Kai | D | HI | U.S. House | 2021 – 2023 |
| | Kaine, Tim | D | VA | U.S. Senate | 2013 – 2025 |
| | Kanjorski, Paul E. | D | PA | U.S. House | 1985 – 2011 |
| | Kaptur, Marcy | D | OH | U.S. House | 1983 – 2023 |
| | Karnes, David Kemp | R | NE | U.S. Senate | 1987 – 1989 |
| | Karst, Raymond Willard | D | MO | U.S. House | 1949 – 1952 |
| | Karsten, Frank Melvin | D | MO | U.S. House | 1947 – 1969 |
| | Karth, Joseph Edward | D | MN | U.S. House | 1959 – 1977 |
| | Kasem, George Albert | D | CA | U.S. House | 1959 – 1961 |
| | Kasich, John R. | R | OH | U.S. House | 1983 – 2001 |
| | Kassebaum, Nancy Landon | R | KS | U.S. Senate | 1979 – 1997 |
| | Kasten, Robert Walter, Jr | R | WI | U.S. Senate | 1975 – 1993 |
| | Kastenmeier, Robert William | D | WI | U.S. House | 1959 – 1991 |
| | Katko, John | R | NY | U.S. House | 2015 – 2023 |
| | Kaufman, Ted | D | DE | U.S. Senate | 2009 – 2011 |
| | Kazen, Abraham, Jr. | D | TX | U.S. House | 1967 – 1985 |
| | Kean, Robert Winthrop | R | NJ | U.S. House | 1945 – 1959 |
| | Kearney, Bernard William | R | NY | U.S. House | 1945 – 1959 |
| | Kearns, Carroll Dudley | R | PA | U.S. House | 1947 – 1963 |
| | Keating, Kenneth Barnard | R | NY | U.S. Senate | 1947 – 1965 |
| | Keating, William John | R | OH | U.S. House | 1971 – 1974 |
| | Keating, William | D | MA | U.S. House | 2011 – 2023 |
| | Kee, James | D | WV | U.S. House | 1965 – 1973 |
| | Kee, John | D | WV | U.S. House | 1945 – 1953 |
| | Kee, Maude Elizabeth | D | WV | U.S. House | 1951 – 1965 |
| | Keefe, Frank Bateman | R | WI | U.S. House | 1939 – 1951 |
| | Keeney, Russell Watson | R | IL | U.S. House | 1957 – 1958 |
| | Kefauver, Carey Estes | D | TN | U.S. Senate | 1945 – 1963 |
| | Keith, Hastings | R | MA | U.S. House | 1959 – 1973 |
| | Keller, Fred | R | PA | U.S. House | 2019 – 2023 |
| | Keller, Ric | R | FL | U.S. House | 2001 – 2009 |
| | Kelley, Augustine Bernard | D | PA | U.S. House | 1941 – 1957 |
| | Kelly, Edna Flannery | D | NY | U.S. House | 1949 – 1969 |
| | Kelly, Edward Austin | D | IL | U.S. House | 1945 – 1947 |
| | Kelly, Mark | D | AZ | U.S. Senate | 2020 – 2023 |
| | Kelly, Mike | R | PA | U.S. House | 2011 – 2023 |
| | Kelly, Richard | R | FL | U.S. House | 1975 – 1981 |
| | Kelly, Robin | D | IL | U.S. House | 2013 – 2023 |
| | Kelly, Sue W | R | NY | U.S. House | 1995 – 2007 |
| | Kelly, Trent | R | MS | U.S. House | 2015 – 2023 |
| | Kem, James Preston | R | MO | U.S. Senate | 1947 – 1953 |
| | Kemp, Jack French | R | NY | U.S. House | 1971 – 1989 |
| | Kempthorne, Dirk | R | ID | U.S. Senate | 1993 – 1999 |
| | Kennedy, Edward M. | D | MA | U.S. Senate | 1963 – 2009 |
| | Kennedy, John Fitzgerald | D | | U.S. President | 1947 – 1963 |
| | Kennedy, John | R | LA | U.S. Senate | 2017 – 2023 |
| | Kennedy, Joseph P., II | D | MA | U.S. House | 1987 – 1999 |
| | Kennedy, Joseph P. | D | MA | U.S. House | 2013 – 2021 |
| | Kennedy, Mark | R | MN | U.S. House | 2001 – 2007 |
| | Kennedy, Patrick J. | D | RI | U.S. House | 1995 – 2011 |
| | Kennedy, Robert Francis | D | NY | U.S. Senate | 1965 – 1968 |
| | Kennelly, Barbara Bailey | D | CT | U.S. House | 1982 – 1999 |
| | Keogh, Eugene James | D | NY | U.S. House | 1945 – 1967 |
| | Kerns, Brian | R | IN | U.S. House | 2001 – 2003 |
| | Kerr, John Hosea | D | NC | U.S. House | 1945 – 1953 |
| | Kerr, Robert Samuel | D | OK | U.S. Senate | 1949 – 1963 |
| | Kerrey, Robert | D | NE | U.S. Senate | 1989 – 2001 |
| | Kerry, John | D | MA | U.S. Senate | 1985 – 2013 |
| | Kersten, Charles Joseph | R | WI | U.S. House | 1947 – 1955 |
| | Ketchum, William Matthew | R | CA | U.S. House | 1973 – 1979 |
| | Keys, Martha Elizabeth | D | KS | U.S. House | 1975 – 1979 |
| | Khanna, Ro | D | CA | U.S. House | 2017 – 2023 |
| | Kihuen, Ruben | D | NV | U.S. House | 2017 – 2019 |
| | Kilburn, Clarence Evans | R | NY | U.S. House | 1945 – 1965 |
| | Kilday, Paul Joseph | D | TX | U.S. House | 1945 – 1961 |
| | Kildee, Dan | D | MI | U.S. House | 2013 – 2023 |
| | Kilgore, Harley Martin | D | WV | U.S. Senate | 1945 – 1956 |
| | Kilgore, Joe Madison | D | TX | U.S. House | 1955 – 1965 |
| | Kilmer, Derek | D | WA | U.S. House | 2013 – 2023 |
| | Kilpatrick, Carolyn Cheeks | D | MI | U.S. House | 1997 – 2011 |
| | Kilroy, Mary Jo | D | OH | U.S. House | 2009 – 2011 |
| | Kim, Andy | D | NJ | U.S. House | 2019 – 2023 |
| | Kim, Jay C. | R | CA | U.S. House | 1993 – 1999 |
| | Kim, Young | R | CA | U.S. House | 2021 – 2023 |
| | Kind, Ron | D | WI | U.S. House | 1997 – 2023 |
| | Kindness, Thomas Norman | R | OH | U.S. House | 1975 – 1987 |
| | King, Angus | I | ME | U.S. Senate | 2013 – 2025 |
| | King, Carleton James | R | NY | U.S. House | 1961 – 1974 |
| | King, Cecil Rhodes | D | CA | U.S. House | 1942 – 1969 |
| | King, David Sjodahl | D | UT | U.S. House | 1959 – 1967 |
| | King, Karl Clarence | R | PA | U.S. House | 1951 – 1957 |
| | King, Peter T. | R | NY | U.S. House | 1993 – 2021 |
| | King, Steve | R | IA | U.S. House | 2003 – 2021 |
| | Kingston, Jack | R | GA | U.S. House | 1993 – 2015 |
| | Kinzer, John Roland | R | PA | U.S. House | 1945 – 1947 |
| | Kinzinger, Adam | R | IL | U.S. House | 2011 – 2023 |
| | Kirk, Mark S. | R | IL | U.S. Senate | 2001 – 2017 |
| | Kirk, Paul G., Jr. | D | MA | U.S. Senate | 2009 – 2010 |
| | Kirkpatrick, Ann | D | AZ | U.S. House | 2009 – 2017 |
| | Kirkpatrick, Ann | D | AZ | U.S. House | 2019 – 2023 |
| | Kirwan, Michael Joseph | D | OH | U.S. House | 1945 – 1970 |
| | Kissell, Larry | D | NC | U.S. House | 2009 – 2013 |
| | Kitchin, Alvin Paul | D | NC | U.S. House | 1957 – 1963 |
| | Kleczka, Gerald D. | D | WI | U.S. House | 1984 – 2005 |
| | Klein, Arthur George | D | NY | U.S. House | 1945 – 1956 |
| | Klein, Herbert C. | D | NJ | U.S. House | 1993 – 1995 |
| | Klein, Ron | D | FL | U.S. House | 2007 – 2011 |
| | Kleppe, Thomas Savig | R | ND | U.S. House | 1967 – 1972 |
| | Kline, John | R | MN | U.S. House | 2003 – 2017 |
| | Klink, Ron | D | PA | U.S. House | 1993 – 2001 |
| | Klobuchar, Amy | D | MN | U.S. Senate | 2007 – 2025 |
| | Kluczynski, John Carl | D | IL | U.S. House | 1951 – 1975 |
| | Klug, Scott L. | R | WI | U.S. House | 1991 – 1999 |
| | Knight, Steve | R | CA | U.S. House | 2015 – 2019 |
| | Knollenberg, Joe | R | MI | U.S. House | 1993 – 2009 |
| | Knowland, William Fife | R | CA | U.S. Senate | 1945 – 1959 |
| | Knox, Victor Alfred | R | MI | U.S. House | 1953 – 1965 |
| | Knutson, Coya Gjesdal | D | MN | U.S. House | 1955 – 1959 |
| | Knutson, Harold | R | MN | U.S. House | 1945 – 1949 |
| | Koch, Edward Irving | D | NY | U.S. House | 1969 – 1977 |
| | Kogovsek, Raymond Peter | D | CO | U.S. House | 1979 – 1985 |
| | Kohl, Herb | D | WI | U.S. Senate | 1989 – 2013 |
| | Kolbe, Jim | R | AZ | U.S. House | 1985 – 2007 |
| | Kolter, Joseph Paul | D | PA | U.S. House | 1983 – 1993 |
| | Konnyu, Ernest Leslie | R | CA | U.S. House | 1987 – 1989 |
| | Kopetski, Michael J. | D | OR | U.S. House | 1991 – 1995 |
| | Kopplemann, Herman Paul | D | CT | U.S. House | 1945 – 1947 |
| | Kornegay, Horace Robinson | D | NC | U.S. House | 1961 – 1969 |
| | Kosmas, Suzanne M. | D | FL | U.S. House | 2009 – 2011 |
| | Kostmayer, Peter Houston | D | PA | U.S. House | 1977 – 1993 |
| | Kowalski, Frank | D | CT | U.S. House | 1959 – 1963 |
| | Kramer, Kenneth Bentley | R | CO | U.S. House | 1979 – 1987 |
| | Kratovil, Frank Jr. | D | MD | U.S. House | 2009 – 2011 |
| | Krebs, John Hans | D | CA | U.S. House | 1975 – 1979 |
| | Krebs, Paul Joseph | D | NJ | U.S. House | 1965 – 1967 |
| | Kreidler, Myron Bradford (Mike) | D | WA | U.S. House | 1993 – 1995 |
| | Krishnamoorthi, Raja | D | IL | U.S. House | 2017 – 2023 |
| | Krueger, Otto | R | ND | U.S. House | 1953 – 1959 |
| | Krueger, Robert Charles | D | TX | U.S. Senate | 1975 – 1993 |
| | Kruse, Edward H. | D | IN | U.S. House | 1949 – 1952 |
| | Kuchel, Thomas Henry | R | CA | U.S. Senate | 1953 – 1969 |
| | Kucinich, Dennis J. | D | OH | U.S. House | 1997 – 2013 |
| | Kuhl, John R. "Randy" Jr. | R | NY | U.S. House | 2005 – 2009 |
| | Kunkel, John Crain | R | PA | U.S. House | 1939 – 1966 |
| | Kupferman, Theodore Roosevelt | R | NY | U.S. House | 1966 – 1969 |
| | Kuster, Ann | D | NH | U.S. House | 2013 – 2023 |
| | Kustoff, David | R | TN | U.S. House | 2017 – 2023 |
| | Kuykendall, Dan Heflin | R | TN | U.S. House | 1967 – 1975 |
| | Kuykendall, Steven | R | CA | U.S. House | 1999 – 2001 |
| | Kyl, John Henry | R | IA | U.S. House | 1959 – 1973 |
| | Kyl, Jon | R | AZ | U.S. Senate | 1987 – 2018 |
| | Kyros, Peter Nicholas | D | ME | U.S. House | 1967 – 1975 |