The 2004 United States elections were held on Tuesday, November 2, 2004, during the early years of the war on terror and after the 2003 invasion of Iraq. Republican President George W. Bush won re-election and Republicans retained control of Congress. Democratic Senator John Kerry of Massachusetts won his party's nomination after defeating Senator John Edwards and several other candidates in the 2004 Democratic presidential primaries. In the general election, Bush won 286 of the 538 electoral votes and 50.7 percent of the popular vote. Foreign policy was the dominant theme throughout the election campaign, particularly Bush's conduct of the war on terrorism and the 2003 invasion of Iraq. Riding Bush's coattails, the Republicans picked up net gains of four Senate seats and three House seats. In the gubernatorial elections, neither party won a net gain of seats. Bush became the first president since Ronald Reagan in 1980 to see his party gain seats in both Houses of Congress during a presidential election year. Republicans would not win another trifecta until 2016. Future President Barack Obama was elected to the United States Senate in Illinois, and he was elected president in the next presidential election. As of 2020, this is the last time the incumbent party retained control over the presidency and Congress after a single term.

Federal elections

President

Republican incumbent President George W. Bush was re-elected, defeating Democratic Senator John Kerry from Massachusetts.

United States Senate

The 34 seats in the United States Senate Class 3 were up for election. Republicans had a net gain of 4 seats.

United States House of Representatives

Republicans gained a couple of seats in the House, mainly due to the 2003 Texas redistricting. Republicans won the national popular vote for the House of Representatives by a margin of 2.6 percentage points.

State elections

Governors

Eleven of the fifty United States governors were up for re-election, as were the governorships of two U.S. territories. The final results were a net change of zero between the political parties. The Democrats picked up the governorships in Montana and New Hampshire, but the Republicans picked up the ones in Indiana and Missouri.

Other statewide elections

In many states where if the following positions were elective offices, voters cast votes for candidates for state executive branch offices of Lieutenant Governor (though some were voted for on the same ticket as the gubernatorial nominee), Secretary of state, state Treasurer, state Auditor, state Attorney General, state Superintendent of Education, Commissioners of Insurance, Agriculture or, Labor, etc.) and state judicial branch offices (seats on state Supreme Courts and, in some states, state appellate courts).

State legislative elections

Initiatives and referendums

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Local elections

Mayoral elections

Some of the major American cities that held their mayoral elections in 2004 included: