The 1804 United States presidential election was the fifth quadrennial presidential election, held from Friday, November 2, to Wednesday, December 5, 1804. Incumbent Democratic-Republican president Thomas Jefferson defeated Federalist Charles Cotesworth Pinckney of South Carolina. It was the first presidential election conducted following the ratification of the Twelfth Amendment to the United States Constitution, which reformed procedures for electing presidents and vice presidents.

The Republican Party, retroactively called the Democratic-Republican Party, and also referred to as the Jeffersonian Republican Party among other names, was an American political party founded by Thomas Jefferson and James Madison in the early 1790s that championed liberalism, republicanism, individual liberty, equal rights, decentralization, free markets, free trade, agrarianism, and sympathy with the French Revolution. The party became increasingly dominant after the 1800 elections as the opposing Federalist Party collapsed.