Origins of the color scheme
The choice of colors reverses a long-standing convention of political colors  whereby red symbols (such as the Red Flag  or Red Star ) are associated with left-wing politics , and right-wing  movements often choose blue as a contrasting color.  Indeed, until the 1980s, Democrats were often represented by red and Republicans by blue. According to The Washington Post , the terms were coined by journalist Tim Russert , during his televised coverage of the 2000 presidential election .  That was not the first election during which the news media  used colored maps to depict voter preferences in the various states, but it was the first time a standard color scheme took hold; the colors were often reversed or different colors used before the 2000 election.
Before the 2000 presidential election, the traditional color-coding scheme was often “Blue for Republican, Red for Democrat,”  in line with European associations, where red  is used for left-leaning parties, and blue for the right. The colors red and blue also are featured on the U.S. flag . Traditional political mapmakers, at least throughout the 20th century, have used blue to represent the modern-day Republicans, as well as the earlier Federalist Party . This may have been a holdover from the American Civil War, during which the predominantly Republican north was considered “blue”.  However, at that time, a maker of widely-sold maps accompanied them with blue pencils in order to mark Confederate force movements, while red was for the union. 
Even earlier, in the 1888 presidential election , Grover Cleveland  and Benjamin Harrison  used maps that coded blue for the Republicans, the color perceived to represent the Union and “Lincoln ‘s Party”, and red for the Democrats. The parties themselves had no official colors, with candidates variously using either or both of the national color palette of red and blue (white being unsuitable for printed materials).
It would be less confusing and only Donald Trump has the clout to begin the reversion to the traditional colors prevalent throughout most of the world where all Leftist, whether communist, fascist, socialists or Nazis would collectively be referred to as the “Red” countries or the “Red” states.
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