Culture File USA: Presidential Elections, Part 3 - Red, Blue & Swing States

The implementation of the "winner-takes-all" electoral system in the USA results in most individual states not splitting their congressional representatives and their electors proportionally among the political contenders but favoring the party with most of the votes.

The color "red" thus represents states which go to the Republican party, and those won by the Democrats are called "blue" states. 

Despite a long history of associating the main political parties with the colors red and blue, modern media broadcast eventually led to today's color coding, most visible in the electoral maps on the screens of TV sets across the country on election night. 

A third group of states is called "purple states"; they are more commonly known as "swing states", alluding to the fact that they can swing either way in terms of results with each election. 

On election night, these states may determine the overall outcome of the election, often by very small margins of a couple of thousand votes, but providing one candidate with the necessary mandates in the Electoral College. 

In the run-up to the election, they turn into battleground states with fierce campaigning from both parties and their candidates. Pennsylvania is among this election cycle's most crucial swing states. 

Resources:

Voice of America: What does it mean to be a red state or a blue state?

CBC News: Why 0.008% of the U.S. population might determine the election