Maybe you don't want to win. Keep getting your 3% every 4 years.
Win what? With Trump?
The GOP has been losing power ever since Clinton, because their most deeply held beliefs (less taxes for the rich, abortion bans, no public health care, more money to big business, no action on climate change) are wildly unpopular. Trump is the extinction burst - the frenzy of activity before the organism actually dies.
It remains to be seen whether they’ll be able to undo democracy to the point that they can stay in power regardless of how unpopular they are, and they have a plausible shot at it. But failing that I think all the gerrymandering in the world won’t be able to keep them around.