Incumbent Democratic-Republican president Thomas Jefferson defeated Federalist Charles Cotesworth Pinckney of South Carolina.

Though Jefferson had only narrowly defeated Adams in 1800, he was widely popular due to the Louisiana Purchase and a strong economy.

American trade boomed due to the temporary suspension of hostilities during the French Revolutionary Wars in Europe, and the Louisiana Purchase was heralded as a great achievement.

The congressional nominating caucus of the Democratic-Republican Party was held in February 1804, with 108 members of the United States Congress in attendance and Senator Stephen R. Bradley as its chair.

The caucus selected to give the vice-presidential nomination to Governor George Clinton whose main opponent was Senator John Breckinridge.

Jefferson was aided by an effective Democratic-Republican party organization, which had continued to develop since 1800, especially in the Federalist stronghold of New England.

As of 2024, Jefferson was the first of eight presidential nominees to win a significant number of electoral votes in at least three elections, the others being Henry Clay, Andrew Jackson, Grover Cleveland, William Jennings Bryan, Franklin D. Roosevelt, Richard Nixon, and Donald Trump.