During the 2004 United States presidential election, concerns were raised about various aspects of the voting process, including whether voting had been made accessible to all those entitled to vote, whether ineligible voters were registered, whether voters were registered multiple times, and whether the votes cast had been correctly counted. More controversial was the charge that these issues might have affected the reported outcome of the presidential election, in which the incumbent, Republican President George W. Bush, defeated the Democratic challenger, Senator John Kerry. Despite the existing controversies, Kerry conceded the election the following day on November 3.
There was generally less attention paid to the Senate and House elections and to various state races, but some of them were also questioned, especially the gubernatorial election in Washington, which was decided by less than 0.01% and involved several recounts and lawsuits. The final recount also reversed the outcome of this election.
In the months leading up to the 2004 election, both parties made efforts to register new voters. In some cases, Republicans challenged or prepared to challenge the validity of many new registrations, citing instances of fictitious names such as Mary Poppins appearing on the voter rolls. Democrats accused the Republicans of using this as an excuse for vote suppression.
There were also complaints about the rejection of registrations by government agencies. College students encountered difficulties in registering where they attended school. Some officials rejected voter registration forms on grounds that were contested, such as a failure to use paper of a particular weight (Ohio) or a failure to check a box on the form (Florida).