Why did Colorado shift so far to the left?

[pbrower2a]

1. Rapid growth of the Hispanic (largely Mexican-American) vote. Republicans have long assumed that as Mexican-Americans assimilate economically they will start showing more concern about taxation and spending, as has typically happened with other economic groups. This said, Mexican-Americans tend to look out for each other; well-off Mexican-Americans do not abandon the poor of their group as white people have done to poor whites in the Mountain South. They are not as atomized as Anglo whites in politics.

Note also that Mexican-American culture also assimilates people not of Mexican-American origin, and not only fellow Hispanics.

2. Colorado has become highly attractive to college-educated people. Its most famous recreational activity, skiing, attracts people of high SES. Today, SES does not clearly link to partisan affiliation as it once did except when the Right goes populist. At one time, high SES largely meant "WASP".. when about every other ethnic group was still (German-Americans possibly excepted) were poor.

Model minorities of all kinds, including middle-class Mexican-Americans, have good cause to distrust a populist demagogue like Donald Trump. I learned as a child that (1) one respects the veteran for his sacrifices, and (2) that one never mocks the handicapped.

People of high SES generally respect veterans and the handicapped.

....Maybe Colorado heads back to the center or even center-right as political coalitions change. That will take time.