1983–1993:

Parts of Erie

1973–1983:

All of Cayuga, Schuyler, Seneca, Yates

Parts of Onondaga, Ontario, Oswego, Steuben, Tompkins

1971–1973:

All of Broome, Chemung, Tioga

Parts of Tompkins

1963–1971:

All of Broome, Chemung, Tioga, Tompkins

1953–1963:

All of Franklin, Lewis, Jefferson, Oswego, St. Lawrence

1945–1953:

All of Clinton, Essex, Saratoga, Warren, Washington

Parts of Rensselaer

1913–1945:

All of Herkimer, Oneida

1903–1913:

All of Seneca, Schuyler, Chemung and Steuben County, New York.^[1]

From 1893–1903 the 33rd district covered all of Erie County except the heavily settled southern portion of the city of Buffalo, New York. Even though about two-thirds of Buffalo's area was in the 33rd District, the 32nd district which had the southern third or so of Buffalo and none of the rest of Erie county had about 6000 more people than the 33rd district.

From 1885–1893 all of Niagara County and all of Erie county except Buffalo had been in the 33rd district. During this time Buffalo was the 32nd district which had 37,000 more people than the 33rd district.

From its formation in 1875 until 1885 the 33rd district had covered Chautauqua and Cattaraugus Counties.

The population of the 33rd's 1903–1913 area was 180,810 in 1900. The population was 0.9% black at this point.^[2]

The following chart shows historic election results. Bold type indicates victor. Italic type indicates incumbent.

• Martis, Kenneth C. (1989). The Historical Atlas of Political Parties in the United States Congress. New York: Macmillan Publishing Company.
• Martis, Kenneth C. (1982). The Historical Atlas of United States Congressional Districts. New York: Macmillan Publishing Company.
• Congressional Biographical Directory of the United States 1774–present
• Election Statistics 1920–present Clerk of the House of Representatives