Prior to the 2000 presidential election, there was no universally recognized color scheme to represent political parties in the United States. ...
Early on, some channels used a scheme of red for Democrats and blue for Republicans. ...
In 2000, for the first time, all major electronic media outlets used the same colors for each party, most likely as a result of the official colors for the presidential candidates, with Gore's campaign using blue lawn signs and imagery and Bush's using red.