Prominent Democrat supporting school from the ground up (5)
I believe the answer is:
noted
'prominent' is the definition.
(I've seen this in another clue)
'democrat supporting school from the ground up' is the wordplay.
'democrat' becomes 'd'.
'supporting' means one lot of letters go next to another (in a down clue, some letters go below others).
'school from the ground' becomes 'eton' (I can't explain this - if you can you should believe this answer much more).
'up' is a reversal indicator (in down clue: letters go upwards).
'eton' in reverse letter order is 'note'.
'd' put after 'note' is 'NOTED'.
Can you help me to learn more?
(Other definitions for noted that I've seen before include "Renowned" , "Celebrity" , "Observed or took account of" , "Well known; registered" , "taken down" .)