Oppose always following one Pole, then another (6)
I believe the answer is:
naysay
'oppose' is the definition.
(naysayers oppose something)
'always following one pole then another' is the wordplay.
'always' becomes 'ay' (archaic term for 'always').
'following' means one lot of letters go next to another.
'one pole' becomes 'n' (abbreviation for North, as in North Pole).
'then another' becomes 'say' (I can't justify this - if you can you should believe this answer much more).
'ay' put after 'n' is 'nay'.
'nay'+'say'='NAYSAY'
(Other definitions for naysay that I've seen before include "Deny" , "refuse" , "refusal" .)