The presidential election on November 7, 2000 was one of the closest presidential elections in the history of the US. It was a contest between Democrat Al Gore, the Vice President, and Republican George W. Bush, Governor of Texas.
On election night, news media twice prematurely declared a winner in Florida based on exit polls, before deciding the race was too close to call.
Both candidates needed Florida's electoral votes to win the presidency. A month of court challenges and recounts folllowed, until the US Supreme Court halted recounts by ruling for Bush by a one vote majority.
Bush was certified as the winner in Florida by a margin of 537 votes, defeating Gore, who received more votes than Bush nationwide. It was the third time in American history that a candidate won the the Electoral College vote without winning the popular vote. (info from Wikipedia)