This is incredibly reductive but suppose there was a single spectrum between progressive and conservative. Let’s make progressive 0 and conservative 10.
Forgetting about parties for a moment, let’s say the will of the general population is 7.
If you have two major parties they will arrange themselves as 6.5 and 7.5. Both parties appear “conservative”, but really your progressive party needs to appear conservative to steal as many swing voters as possible.
If they won consecutive elections their policies would start to move back down the spectrum.
That’s not really how major parties work though?
This is incredibly reductive but suppose there was a single spectrum between progressive and conservative. Let’s make progressive 0 and conservative 10.
Forgetting about parties for a moment, let’s say the will of the general population is 7.
If you have two major parties they will arrange themselves as 6.5 and 7.5. Both parties appear “conservative”, but really your progressive party needs to appear conservative to steal as many swing voters as possible.
If they won consecutive elections their policies would start to move back down the spectrum.
This is known as the “Overton window” for anyone who wants to read into it further.