The 1804–05 United States House of Representatives elections were held on various dates in various states between April 24, 1804 (in New York) and August 5, 1805 (in Tennessee). Each state set its own date for its elections to the House of Representatives before the first session of the 9th United States Congress convened on December 2, 1805. The elections occurred at the same time as PresidentThomas Jefferson's re-election. Elections were held for all 142 seats, representing 17 states.
Under Jefferson's popular administration, his party continued to gain seats in the House. Territorial acquisitions from the Louisiana Purchase and economic expansion gave voters a positive view of the Democratic-Republicans, whose majority, already commanding in the 8th Congress, now surpassed three-quarters of the total membership. Following this election, Federalists were able to secure few seats outside of New England and party legitimacy deteriorated as political thought turned away from Federalist ideals perceived to be elitist and anti-democratic.
Incumbent resigned February 22, 1804. New member electedApril 24–26, 1804.[1] Democratic-Republican hold. Successor seated November 5, 1804.[2] Successor was not elected to the next term on the same ballot, see below.
Incumbent resigned August 10, 1804. New member electedSeptember 17, 1804.[1] Democratic-Republican hold. Successor seated November 5, 1804.[2] Successor was not a candidate for the next term, see below.
Incumbent died March 7, 1804. New member electedOctober 1, 1804.[1] Democratic-Republican hold. Successor seated November 6, 1804.[2] Successor was also elected on the same day to the next term, see below.
Incumbent died May 17, 1804. New member electedOctober 1804.[1] Democratic-Republican hold. Successor seated November 5, 1804.[2] Successor was later elected to the next term, see below.
Incumbent resigned October 15, 1804. New member electedNovember 2, 1804 to finish his brother's term.[1] Democratic-Republican hold. Successor seated November 27, 1804.[2] Successor was not a candidate to the next term, see below.
Incumbent resigned to become U.S. Senator. New member electedNovember 13, 1804.[1] Democratic-Republican hold. Successor seated December 4, 1804.[2] Successor was later elected to the next term, see below.
Incumbent resigned November 22, 1804 to become U.S. Senator. New member electedJanuary 2–4, 1805.[1] Democratic-Republican hold. Successor seated February 14, 1805.[2] Successor was also elected on the same day to the next term, see below.
Representative-elect declined the seat to become associate justice of the New York Supreme Court. New member electedSeptember 11–13, 1804.[1] Democratic-Republican hold. Successor seated December 2, 1805.[10]
Incumbent resigned November 22, 1804 to become U.S. Senator. New member electedJanuary 2–4, 1805.[1] Democratic-Republican hold. Successor seated December 2, 1805.[10] Successor was also elected on the same day to finish the previous term, see above.
Incumbent died March 7, 1804. New member elected. Democratic-Republican hold. Successor was also elected on the same day to finish the current term, see above.
New York held elections for the 9th Congress on April 24–26, 1804. For this year and the next election year, the 2nd and 3rd districts had combined returns, effectively a plural district with 2 seats, though still numbered as separate districts. At the time, District 2 consisted of only part of New York County, while District 3 consisted of the remainder of New York County plus Kings and Richmond Counties. By consolidating the two, it ensured that New York County would be combined into a single district.
Vermont required a majority for election, which frequently mandated runoff elections. The 2nd, and 3rd districts both required second elections in this election cycle, and districts both required second elections in this election cyclethe 3rd district required a third election.
There were three territories with non-voting delegates in the 9th Congress, one of which (the Orleans Territory) did not send its first representative until 1806. The delegates were elected by the territorial legislatures, votes here are the number of members of the territorial legislatures voting for each candidate.
In the Mississippi Territory, the territorial legislature was locked. The first vote given above was on the 7th ballot, after which point the territorial legislature adjourned, the second vote was at a later session of the territorial legislature.
^ ab Date given for the start of the term, of the person elected at the special election (source: Congressional Biographical Directory). In some cases this is clearly wrong as the date of the legal start of the Congress is given, even though the member was elected at a later date.