Depending on which person, persons or organization created the particular “map” in question, red has sometimes meant Democrat and blue has sometimes meant Republican, and vice-versa. It’s been since approximately the 1860s that such designations were first used, and for more than 100 years, they have changed back and forth almost as often as the weather has changed.
[P.S. It’s perfectly ok to be confused as to which color means which political party.]
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