1804–05 United States Senate elections

← 1802 & 1803 Dates vary by state 1806 & 1807 →
11 of the 34 seats in the United States Senate (plus special elections) 18 seats needed for a majority
Majority party Minority party   Party Democratic-Republican Federalist Last election 22 seats 9 seats Seats before 25 9 Seats won 9 2 Seats after 27 7 Seat change 2 2 Seats up 7 4
Results:      Dem-Republican hold      Dem-Republican gain      Federalist hold
Majority Party before election Democratic-Republican Elected Majority Party Democratic-Republican

The 1804–05 United States Senate elections were held on various dates in various states. As these U.S. Senate elections were prior to the ratification of the Seventeenth Amendment in 1913, senators were chosen by state legislatures. Senators were elected over a wide range of time throughout 1804 and 1805, and a seat may have been filled months late or remained vacant due to legislative deadlock.^[1] In these elections, terms were up for the senators in Class 2.

These elections expanded the Democratic-Republican Party's overwhelming control over the Senate. The Federalists went into the elections with such a small share of Senate seats (9 out of 34, or 27%) that even if they had won every election, they would have still remained a minority caucus.

Results summary

Senate party division, 9th Congress (1805–1807)

• Majority party: Democratic-Republican (27)
• Minority party: Federalist (7)
• Other parties: 0
• Total seats: 34

Change in composition

Only reflects results of regular elections.

Before the regular elections

Result of the regular elections