75 years?
Yes, take a look at the history and problems of immigration in America.
We started importing large numbers of European thinking, even anti-Protestant Christian liberal voters in the mid 1800s.
Look at what they were doing to American politics then, and what we see today, they started a progression towards the left that fed itself with imported voters, which led to more despised immigration, which kept feeding the voting machine for the left, nothing has changed, and over generations, they won.