The District of Columbia voted by an extremely large margin in favor of the Democratic candidate John F. Kerry, with a margin of victory of 79.84% over the incumbent George W. Bush, more than any state and in the history of the district. That can be attributed to the fact that D.C. only encompasses an urban core area (and those are generally very liberal in nature). A recent San Francisco study based on the 2004 presidential election exit polls, ranked the District of Columbia as the 4th most liberal city in the country. This information supports the fact that the District of Columbia has never voted for a Republican.
Technically the voters of D.C. cast their ballots for electors: representatives to the Electoral College. D.C. is allocated 3 electors. All candidates who appear on the ballot or qualify to receive write-in votes must submit a list of 3 electors, who pledge to vote for their candidate and his or her running mate. Whoever wins the majority of votes in the state is awarded all 3 electoral votes. Their chosen electors then vote for President and Vice President. Although electors are pledged to their candidate and running mate, they are not obligated to vote for them. An elector who votes for someone other than his or her candidate is known as a faithless elector.
The electors of each state and the District of Columbia met on December 13, 2004 to cast their votes for President and Vice President. The Electoral College itself never meets as one body. Instead the electors from each state and the District of Columbia met in their respective capitols.
The following were the members of the Electoral College from D.C. All were pledged to and voted for John Kerry and John Edwards.