Smithsonian racconta come si è arrivati a identificare gli stati vinti dai democratici con il colore blu e dai repubblicani con il rosso durante le elezioni presidenziali.
Prima delle elezioni del 2000, vinte all'ultimo riconteggio da George W. Bush, non esisteva nessuna consuetudine e i media alternavano le tonalità cromatiche di volta in volta.
Proprio il perdurarsi per settimane di quella situazione di incertezza, con una conseguente sovraesposizione delle mappe sui media, pose un punto fermo nella scelta dei colori elettorali per gli anni a venire.
In 1976, when NBC debuted its mammoth electronic map, ABC News employed a small, rudimentary version that used yellow for Ford, blue for Carter and red for states in which votes had yet to be tallied. In 1980, NBC once again used red for Carter and blue for the Republican challenger, Ronald Reagan, and CBS followed suit. But ABC flipped the colors and promised to use orange for states won by John Anderson, the third-party candidate who received 6.6% of the popular vote. (Anderson carried no states, and orange seems to have gone by the wayside.) Four years later, ABC and CBS used red for Republicans and blue for Democrats, but the combination wouldn't stick for another 16 years. During the four presidential elections Wetzel oversaw for NBC, from 1976 through 1988, the network never switched colors. Republicans were cool blue, Democrats hot red.
[...] Two days after voters went to the polls in 2000, both the New York Times and USA Today published their first color-coded, county-by-county maps detailing the showdown between Al Gore and George W. Bush. Both papers used red for the Republican Bush, blue for the Democrat Gore.
"I just decided red begins with 'r,' Republican begins with 'r.' It was a more natural association," said Archie Tse, senior graphics editor for the Times. "There wasn't much discussion about it."
Paul Overberg, a database editor who designed the map for USA Today, said he was following a trend: "The reason I did it was because everybody was already doing it that way at that point."
And everybody had to continue doing it for a long time. The 2000 election dragged on until mid-December, until the Supreme Court declared Bush the victor. For weeks, the maps were ubiquitous.
Perhaps that's why the 2000 colors stuck. Along with images of Florida elections officials eyeballing tiny ballot chads, the maps were there constantly, reminding us of the vast, nearly even divide between, well, red and blue voters.
From an aesthetic standpoint, Overberg said, the current color scheme fits with the political landscape. Republicans typically dominate in larger, less populated states in the Plains and Mountain West, meaning the center of the United States is very red. "If it had been flipped, the map would have been too dark," he said. "The blue would have been swamping the red. Red is a lighter color."