Monstrous female Democrat upset America (6)
I believe the answer is:
medusa
'monstrous female' is the definition.
'medusa' can be an answer for 'female' (I have seen 'Hideous female' mean 'medusa' so perhaps 'female' could also mean 'medusa'). I'm not certain of the 'monstrous' bit.
'democrat upset america' is the wordplay.
'democrat' becomes 'dem' (common abbreviation in US politics).
'upset' says the letters should be written in reverse.
'america' becomes 'usa' (synonyms).
'dem' written backwards gives 'med'.
'med'+'usa'='MEDUSA'
Can you help me to learn more?
(Other definitions for medusa that I've seen before include "Gorgon of Greek myth" , "Mythological gorgon" , "Amused (anag)" , "Mythical woman with snakes for hair" , "One of three sisters with snakes for hair" .)