General agreement excludes Tory count (6)
I believe the answer is:
census
'count' is the definition.
(census is a kind of count)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for census that I've seen before include "Periodic count by statisticians" , "Head-count" , "Periodic counting of the population" , "Official survey" , "Periodic count as of population" .)