At some point in the 21st century, we will have an extremely unpopular Democratic president who will put all of safe/solid D states in play. Polarization isn’t going to last forever, and I assume we will revert to the mean and get back to having alternating landslides in presidential elections.
Bush's 25% approval rating, extremely unpopular Middle East quagmires, botched Katrina response, and even topping it off with an economic collapse less than 2 months (!) before the election didn't put safe R states into play unless you count Indiana. I don't see it happening.
