Coy about admitting backing politically correct party to secure university tenure (9)

I believe the answer is:

occupancy

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'tenure' is the definition.
(I've seen this before)

I don't understand the rest of the clue.

(Other definitions for occupancy that I've seen before include "Tenancy" , "Tenure" , "The proportion of a hotel in use" , "Residence" , "possession" .)

I've seen this clue in The Independent.

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