Conservative turncoat in terribly miserable old political group (7,9)

'terribly miserable old political group' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'conservative turncoat' is the wordplay.
I cannot quite see how this works, but
'conservative' could be 'c' (UK political abbreviation) and 'c' is present in the answer.
'turncoat' could be 'rat' (I've seen this in another clue) and 'rat' is located in the answer.
This may be the basis of the clue (or it may be nonsense).

'in' is the link.

Can you help me to learn more?