Often seen as one of the key swing states, the largest bellwether state Florida figured heavily during the 1876 and 2000 presidential elections.
Although it is not disputed that Tilden outpolled Hayes in the popular vote, after a first count of votes, Tilden had won 184 electoral votes to Hayes's 165, with 20 votes from four states unresolved: in Florida, Louisiana, and South Carolina, each party reported its candidate had won the state, while in Oregon, one elector was replaced after being declared illegal for being an "elected or appointed official". In Florida (with 4 electoral votes), Louisiana (with 8) and South Carolina (with 7), reported returns favored Tilden, but the elections in each state were marked by electoral fraud and threats of violence against Republican voters; the most extreme case was in South Carolina, where an impossible 101 percent of all eligible voters in the state had their votes counted. Each of the disputed state election cases (Florida, Louisiana, Oregon, and South Carolina) was respectively submitted to the commission by Congress. The returns accepted by the Commission put Hayes' margin of victory in South Carolina at 889 votes, the second-closest popular vote margin in a decisive state in U.S. history, after the election of 2000, which was decided by 537 votes in Florida: in 2000, the margin of victory in the Electoral College for George W. Bush was five votes, as opposed to Hayes' one vote. On election night, it was unclear who had won, with the electoral votes of the state of Florida still undecided. The returns showed that Bush had won Florida by such a close margin that state law required a recount. The recount having been ended, Bush won Florida by 537 votes, a margin of 0.009%. This was also the only time since 1944 that Ohio did not vote the same way as Florida, a bellwether state just like Ohio. Florida has backed the winning candidate from 1996 to 2016, the longest active streak of any state except Ohio, and has only backed the losing candidate three times since 1928. Since the mid-20th century, Florida has been considered a bellwether, voting for 15 successful presidential candidates since 1952. 
