If Cruz and Paul stay true to themselves, they'll be fine
The hillaristas are getting old, along with hillary. They aren't going to appeal to younger voters. TedCruz and RandPaul are appealing to a younger generation, who mostly blame hillary and her peers for the mess the US is in now. And Bill Clinton? He hasn't been president since 2000. Younger voters were in elementary school then.
They may be getting older but they are also becoming more shrill.