Swing states

In United States presidential politics, a swing state (also, battleground state or purple state) is a state in which no single candidate or party has overwhelming support in securing that state's electoral college votes.

Purple 이라고 불리는 이유가 재미있다.
Purple state, so named because purple is the combination of the colors red and blue, which are used to represent Republican- and Democratic-majority states, respectively.


http://en.wikipedia.org/wiki/Swing_state
http://history.howstuffworks.com/american-history/swing-state2.htm