Try this one on for size. Your party's regressive policies that resonated with an older crowd that grew fat and rich off the post-war boom in the US is dying, and the younger generations are starting to see right through your bullshit. No real wage growth, no real improvement in quality of life, no real prospects for achieving the same things that your core constituency got. The tricks you've been playing with electoral districts and gerrymandering are not working as well anymore because the deck is so stacked against you. Now you're wondering why you're losing power after courting the chaff of the electorate.
The choice whether to change, or to be annihilated is yours. Frankly, I wouldn't mind you staying the course to your own oblivion.