Though you've already been here for three months, welcome to TalkBass, BassShmuck!
Before posting a thread, please remember to search the forums. This is a song which, even very recently, has had a number of discussions which described his tone in great detail.
To answer your question, no one but himself, the group, and the engineers for the album are 100% certain on how he achieves it. However, this details some of the effects he uses to attain it:
Electro-Harmonix Russian Big Muff Pi (Green Sovtek version)
Akai Deep Impact SB-1 Synthesizer
Human Gear Animato Distortion (ProCo RAT Clone)
Distortion on Marshall DB400 Amp
Clean Blend
You can approximate the tone decently well by using a blended Big Muff (the Electro-Harmonix Bass Big Muff may suffice), a blended overdrive of some kind (Boss ODB-3 or Ibanez PD7), and a blended synthesizer (Boss SYB series, Ibanez SB7, Digitech Bass Synth Wah)
The most obvious and noted portion of his tone is the Big Muff, so you may find a Bass Big Muff will get you where you want to be if you don't want to spend too much money.
Hope that helps.