This is the main Bass riff with slight variations throughout. Hope it helps.
 
   Am 
G|---------------|---------------|---------------|---------------| 
D|---------------|---------------|---------------|---------------| 
A|-0---0---------|-0---0---------|-0---0---------|-0---0---------| 
E|-------0--3--4-|-------0--0-3--|-------0--3--4-|-------0--0-3--| 
			
   Am                D/F#              E    F#7    Gm   G#m 
G|-----------------|-----------------|-----------|------------------| 
D|-----------------|-----0-4---------|-----------|--------------0-2-| 
A|0---0------------|-----------5-0---|-----------|--------0-2-3-----| 
E|------0--3-5-4-3-|-2-------------2-|-0----2----|-3----4-----------|