Apart from the extreme violence, is the zombie genre fundamentally liberal or conservative? Does its increasing popularity serve anyone's political ends?

While one can certainly use zombies to express all kinds of ideas, I would argue that at heart, the genre is a progressive one. It's true that fighting off the zombie horde requires plentiful firearms, no doubt pleasing Second Amendment advocates. And in a zombie movie, government tends to be either ineffectual or completely absent. On the other hand, when the zombie apocalypse comes, capitalism breaks down, too -- people aren't going to be exchanging money for goods and services; they're just going to break into the hardware store and grab what they need

But most important, what ensures survival in a zombie story are the progressive ideals of common cause and collective action.