| Name: | First Elected or Appointed: |
| Iannacci, Angela G. | November 8, 2005 |
| Imrie, Daniel F. | November 4, 1941 |
| Ingalls, Charles R. | November 3, 1863 |
| Inglehart, George C. | November 4, 1975 |
| Ingraham, Daniel P. | November 3, 1857 |
| Ingraham, George L. | November 3, 1891 |
| Ingraham, Irad S. | November 6, 1984 |
| Ingraham, Phoenix | November 6, 1923 |
| Ingrassia, Angelo J. | November 2, 1982 |
| Isseks, Abraham S. | November 6, 1979 |