The 2000 election between George W. Bush, the Republican candidate, and Democratic candidate Al Gore remains controversial because the vote between the two candidates was so close. The election was so tight, and only about 500 votes separated the candidates in Florida, the state on which the outcome of the election rested. With so many Florida ballots questionable, the decision as to who actually won landed in the Supreme Court.
The Supreme Court decided on Bush by a 5-4 vote, which some people felt divided on party lines, calling into question the supposedly non-partisan nature of the nation's highest court. If the vote had been 9-0 or 8-1, it would have been less controversial. The split vote, however, revealed the Supreme's Court uncertainty.
Further, the election was controversial because some methods of counting the ballots gave Florida to Gore and because Gore won the popular vote nationwide.
Finally, the impact of third party Green candidate Ralph Nader created controversy, with some contending that his campaign cost Gore the votes he needed to win Florida and others arguing that the election would not have been so close if Gore had not fumbled on his own.
Since elections have consequences, and since the U.S. has a strong ideological commitment to universal suffrage and democracy, the 2000 election left many people uneasy.