Summons late in the day succeeded securing approval (6)
I believe the answer is:
evokes
'summons' is the definition.
(evoking is a kind of summoning)
'late in the day succeeded securing approval' is the wordplay.
I cannot really see how this works, but
'succeeded' could be 's' (genealogical abbreviation) and 's' is found in the answer.
'approval' could be 'ok' (OK is an example) and 'ok' is found within the answer.
'day' could be 'eve' (eve is a kind of day) and 'eve' is found in the leftover letters.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for evokes that I've seen before include "Elicits (a response)" , "Draws forth from memory" , "Brings to mind" , "Calls up, say memories" , "Summons up" .)