Due to a technicality, the election of 1800 resulted in a tie between Thomas Jefferson and Aaron Burr, Jefferson's vice presidential running mate. After several months, the U.S. House of Representatives certified Jefferson as the winner, but the confusion prompted a clarification of voting procedures, which resulted in the Twelfth Amendment to the Constitution.
Although Andrew Jackson won the popular vote in 1824, neither he nor his opponent, John Quincy Adams, won a majority in the electoral college. When the House finally chose Adams, Jackson became the first presidential candidate to win the popular vote but lose the election.
Samuel Tilden won the national popular vote in 1876, but a close race in Florida swung the majority of electoral votes to Rutherford B. Hayes. A special congressional commission, voting along party lines, finally awarded the presidency to Hayes.
Although Grover Cleveland, the incumbent president, won the national popular vote in 1888, Benjamin Harrison won the presidency with a majority in the electoral college.
A stalemate in Florida held up the 2000 election results between Al Gore and George W. Bush for five weeks after the election. The U.S. Supreme Court finally intervened, settling the election in favor of Bush, even though Gore had won the national popular vote.