The United States Senate elections of 1804 and 1805 were elections that expanded the Democratic-Republican Party's overwhelming control over the United States 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. As these elections were prior to the ratification of the seventeenth amendment, senators were chosen by state legislatures.