Missouri, the “Show Me” State, the state of President Harry Truman, has been a bellwether state since 1904.
From 1904 to 2004, Missouri voted with the winner every time except 1956, when Adlai Stevenson defeated Dwight D. Eisenhower by 4,000 votes.
In 2008, like in 1956, they voted for the losing Presidential nominee, John McCain, over Barack Obama, but again by only about 4,000 votes.
In 2012, however, the bellwether reputation was harmed when Mitt Romney won over Barack Obama by 259,000 votes!
Presently, Hillary Clinton is shown as leading Donald Trump for the election in Missouri, so if they end up as the nominees of their parties, and the polls stay consistent, then Missouri will return to being a bellwether state, assuming that Clinton wins the Presidency, which is highly likely!
Missouri is not considered a “swing” state, but it could be part of the winning party’s majority for the 26th out of the last 29 national elections for the Presidency!