There is a train of thought that says it is the lib’s that are in decline due to the birth rate and that we might even duck the bullet of being a minority party (immigration)because of it.
This is actually accepted by quite a number of thinkers on the right.
The liberals have the demographic advantage in the short term, but it will shift the other way in the second half of this century.
We won't live to see it however and if they get total power alot of permanent damage can be done.