He was elected as a Republican to the 63rd, 64th, 65th, 66th and 67th United States Congresses, holding office from March 4, 1913 to March 3, 1923. He was an alternate delegate to the 1920 Republican National Convention.
He was interred in a family mausoleum in Mount Hope Cemetery, Rochester. The Tiffany window from the mausoleum is on display at the Memorial Art Gallery, Rochester.
- United States Congress. "Thomas B. Dunn (id: D000553)". Biographical Directory of the United States Congress.
| New York State Senate
George L. Meade
| New York State Treasurer
John J. Kennedy
|U.S. House of Representatives|
| Member of the U.S. House of Representatives
from New York's 38th congressional district