The bass line on this song is pretty easy. 
But sounds so groovy. 
In the song the bass player, Michael Ivins uses some type of distortion pedal. 

Main Riff (00:08-00:35)
G|--------------------------------------------------------|
D|------------3-----------3----------3----------3---------|
A|-------3h5----5----3h5----5---3h5----3----3h5----5------|
E|--------------------------------------------------------|

Chorus(00:36-1:00)
G|-------------------------------------------------------|
D|-------------------------------------------------------|
A|----5----5----5----5----5----5----5---5----5----5------|
E|-------------------------------------------------------|

then repeat the main riff and chorus


Interlude? (1:58-2:50)
G|---------------------------------|
D|---0-0-3---0-0-3---0-0-3---0-0-3-|
A|---------------------------------|
E|---------------------------------|

G|---------------------------------|
D|---0-0----0-0----0-0----0-0------|
A|---------------------------------|
E|-------1-------1------1-----1----|

then repeat main riff and chorus
Closing Riff
(3:45-4:35)
G|--------------------------------------------------------------|
D|------------3-----------3----------3----------3-----------3---|
A|-------3h5----5----3h5----5---3h5----3----3h5----5----3h5---5-|
E|--------------------------------------------------------------|

G|--------------------------------------------------------------|
D|------------3-----------3----------3----------3-----------3---|
A|-------3h5----5----3h5----5---3h5----3----3h5----2----3h5---1-|
E|--------------------------------------------------------------|

G|-----------------------------------------------------------|
D|------------3-----------3--------3--------3--------3-------|
A|-------3h5--------3h5-------3h5-------3h5------3h5---5-----|
E|--------------5-----------4--------3--------2--------------|