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 President Thomas 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 which were perceived to be elitist and anti-democratic.

Election summaries + ↓ 114 28 Democratic-Republican Federalist

State Type Date Totalseats Democratic-Republican Federalist Seats Change Seats Change New York Districts April 24–26, 1804 17 15 3 2 3 Kentucky Districts August 6, 1804 6 6 0 North Carolina Districts August 10, 1804 12 12 1 0 1 New Hampshire At-large August 27, 1804 5 0 5 Rhode Island At-large August 28, 1804 2 2 0 Vermont Districts September 4, 1804 4 2 1 2 1 Connecticut At-large September 17, 1804 7 0 7 Maryland Districts October 1, 1804 9 7 1 2 1 Delaware At-large October 2, 1804 1 0 1 1 1 Georgia At-large October 2, 1804 4 4 0 South Carolina Districts October 8–9, 1804 8 8 2 0 2 Ohio At-large October 9, 1804 1 1 0 Pennsylvania Districts October 9, 1804 18 17 1 1 1 Massachusetts Districts November 5, 1804 17 10 3 7 3 New Jersey At-large November 6–7, 1804 6 6 0 Late elections (after the March 4, 1805, beginning of the next Congress) Virginia Districts April 1805 22 21 3 1 3 Tennessee Districts August 4–5, 1805 3 3 0 Total 142 114 11 28 11

Special elections

There were special elections in 1804 and 1805 during the 8th United States Congress and 9th United States Congress.

Elections are sorted here by date then district.

8th Congress District Incumbent This race Representative Party First elected Results Candidates John Smith Democratic-Republican 1799 Incumbent resigned February 22, 1804.New member elected April 24–26, 1804 and seated November 5, 1804.8th Congress membership roster Democratic-Republican hold.Winner was not elected to the next term on the same ballot; see below. Thomson J. Skinner Democratic-Republican 1796 1799 1803 Incumbent resigned August 10, 1804.New member elected September 17, 1804 and seated November 5, 1804.Democratic-Republican hold.Winner was not a candidate for the next term; see below. Daniel Hiester Democratic-Republican 1788 (Penn.)1796 1801 (Md.) Incumbent died March 7, 1804.New member elected October 1, 1804 and seated November 6, 1804.Democratic-Republican hold.Winner was also elected to the next term; see below. John Johns Trigg Democratic-Republican 1803 Incumbent died May 17, 1804.New member elected in October 1804 and seated November 5, 1804.Democratic-Republican hold.Winner was later elected to the next term; see below. William Hoge Democratic-Republican 1802 Incumbent resigned October 15, 1804.New member elected November 2, 1804 to finish his brother's term and seated November 27, 1804.Democratic-Republican hold.Winner was not a candidate to the next term; see below. Andrew Moore Democratic-Republican 1789 Incumbent resigned to become U.S. Senator.New member elected November 13, 1804 and seated December 4, 1804.Democratic-Republican hold.Winner was later elected to the next term; see below. Samuel L. Mitchill Democratic-Republican 1800 Incumbent resigned November 22, 1804 to become U.S. Senator.New member elected January 2–4, 1805 and seated February 14, 1805.Democratic-Republican hold.Winner was also elected to the next term; see below.

9th Congress District Incumbent This race Representative Party First elected Results Candidates Daniel D. Tompkins Democratic-Republican 1804 Representative-elect declined the seat to become associate justice of the New York Supreme Court.New member elected September 11–13, 1804 and seated December 2, 1805.Democratic-Republican hold. Samuel L. Mitchill Democratic-Republican 1800 Incumbent resigned November 22, 1804 to become U.S. Senator.New member elected January 2–4, 1805 and seated December 2, 1805.Democratic-Republican hold.Winner was also elected to finish the previous term; see above. James Gillespie Democratic-Republican 17931799 1803 Representative-elect died January 5, 1805.New member elected August 8, 1805 and seated December 2, 1805.Democratic-Republican hold. Calvin Goddard Federalist 1801 Both incumbents/representatives-elect resigned.New members elected September 16, 1805 and seated December 2 and 10, 1805.Federalist holds. Roger Griswold Federalist 1794 John B. Earle Democratic-Republican 1803 Incumbent/representative-elect resigned.New member elected September 26–27, 1805.Democratic-Republican hold. James A. Bayard Sr. Federalist 1796 Representative-elect declined the seat to become U.S. Senator.New member elected October 1, 1805.Federalist hold. John A. Hanna Democratic-Republican 1796 Representative-elect died July 23, 1805.New member elected October 8, 1805.Democratic-Republican hold. John B. C. Lucas Democratic-Republican 1802 Representative-elect declined the seat.New member elected October 8, 1805 and seated December 2, 1805.Democratic-Republican hold. None (district created). New delegate elected December 12, 1805.Federalist gain.

Third ballot

Connecticut

District Incumbent Party Firstelected Result Candidates Calvin Goddard Federalist 1801 Incumbent re-elected but declined to serve, leading to a special election, see above. Samuel W. Dana Federalist 1796 Incumbent re-elected. John Davenport Federalist 1798 Incumbent re-elected. Roger Griswold Federalist 1794 Incumbent re-elected but declined to serve, leading to a special election, see above. Benjamin Tallmadge Federalist 1801 Incumbent re-elected. John Cotton Smith Federalist 1800 Incumbent re-elected. Simeon Baldwin Federalist 1803 Incumbent retired.New member elected.Federalist hold.

Delaware

District Incumbent Party Firstelected Result Candidates Caesar A. Rodney Democratic-Republican 1802 Incumbent lost re-election.Federalist gain.Successor declined to serve, leading to a special election; see above.

Georgia

District Incumbent Party Firstelected Result Candidates Peter Early Democratic-Republican 1802 Incumbent re-elected. David Meriwether Democratic-Republican 1802 Incumbent re-elected. Joseph Bryan Democratic-Republican 1802 Incumbent re-elected. Samuel Hammond Democratic-Republican 1802 Incumbent retired.Democratic-Republican hold.Election was later contested and a new successor named.

Indiana Territory See Non-voting delegates, below.

Kentucky

District Incumbent Party Firstelected Result Candidates Matthew Lyon Democratic-Republican 1797 1803 Incumbent re-elected. John Boyle Democratic-Republican 1803 Incumbent re-elected. Matthew Walton Democratic-Republican 1803 Incumbent re-elected. Thomas Sandford Democratic-Republican 1803 Incumbent re-elected. John Fowler Democratic-Republican 1797 Incumbent re-elected. George M. Bedinger Democratic-Republican 1803 Incumbent re-elected.

Maryland

District Incumbent Party Firstelected Result Candidates John Campbell Federalist 1801 Incumbent re-elected. Walter Bowie Democratic-Republican 1802 Incumbent retired.Democratic-Republican hold. Thomas Plater Federalist 1801 Incumbent lost re-election.Democratic-Republican gain. Daniel Hiester Democratic-Republican 1788 1796 1801 Incumbent died March 7, 1804.Democratic-Republican hold.Successor was also elected on the same day to finish the current term; see above. Nicholas R. Moore Democratic-Republican 1803 Incumbent re-elected. William McCreery Democratic-Republican 1803 Incumbent re-elected. John Archer Democratic-Republican 1801 Incumbent re-elected. Joseph H. Nicholson Democratic-Republican 1798 Incumbent re-elected. John Dennis Federalist 1796 Incumbent retired.Federalist hold.

Massachusetts

The majority requirement was met in all 17 districts in the 1804 elections. District Incumbent Party Firstelected Result Candidates William Eustis Democratic-Republican 1801 Incumbent lost re-election.Federalist gain. Jacob Crowninshield Democratic-Republican 1803 Incumbent re-elected. Manasseh Cutler Federalist 1801 Incumbent retired.Federalist hold. Joseph Bradley Varnum Democratic-Republican 1794 Incumbent re-elected. Thomas Dwight Federalist 1803 Incumbent retired.Federalist hold. Samuel Taggart Federalist 1803 Incumbent re-elected. Nahum Mitchell Federalist 1803 Incumbent lost re-election.Democratic-Republican gain. Lemuel Williams Federalist 1798 Incumbent lost re-election.Democratic-Republican gain. Phanuel Bishop Democratic-Republican 1798 Incumbent re-elected. Seth Hastings Federalist 1801 Incumbent re-elected. William Stedman Federalist 1803 Incumbent re-elected. Simon Larned Democratic-Republican 1804 Incumbent retired.Democratic-Republican hold. Ebenezer Seaver Democratic-Republican 1803 Incumbent re-elected. Richard Cutts Democratic-Republican 1801 Incumbent re-elected. Peleg Wadsworth Federalist 1792 Incumbent re-elected. Samuel Thatcher Federalist 1802 Incumbent lost re-election.Democratic-Republican gain. Phineas Bruce Federalist 1803 Incumbent retired.Democratic-Republican gain.

Mississippi Territory See Non-voting delegates, below.

New Hampshire

District Incumbent Party Firstelected Result Candidates Silas Betton Federalist 1802 Incumbent re-elected. Samuel Hunt Federalist 1802 Incumbent retired.Federalist hold. Samuel Tenney Federalist 1800 Incumbent re-elected. David Hough Federalist 1802 Incumbent re-elected. Clifton Clagett Federalist 1802 Incumbent retired.Federalist hold.

New Jersey

The Federalist ticket was announced only a week before the election, with no active campaigning.

District Incumbent Party Firstelected Result Candidates Adam Boyd Democratic-Republican 1803 Incumbent retired.Democratic-Republican hold. Ebenezer Elmer Democratic-Republican 1800 Incumbent re-elected. William Helms Democratic-Republican 1800 Incumbent re-elected. James Mott Democratic-Republican 1800 Incumbent retired.Democratic-Republican hold. Henry Southard Democratic-Republican 1800 Incumbent re-elected. James Sloan Democratic-Republican 1803 Incumbent re-elected.

New York

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.