Overthrow Crown with half the people (6)
I believe the answer is:
topple
'overthrow' is the definition.
(I've seen this before)
'crown with half the people' is the wordplay.
'crown' becomes 'top' ('top' can be a synonym of 'crown'**).
'with' says to put letters next to each other.
'half' means to take half the letters.
'people' cut in half is 'ple'.
'top'+'ple'='TOPPLE'
(Other definitions for topple that I've seen before include "Overthrow or fall headlong" , "Overthrow, cause to fall" , "Overbalance and fall headlong" , "(Cause to) tip over" , "dethroned" .)