Member's Circle In Attempt To Get Boris Overturned (4,2)

[mjhall]

Help please on 23d "Member's circle in attempt to get Boris overturned" (4,2).
T?R? M?
The answer could be TORY MP, but I am not sure why. I realise TRY is part of this.

[Toorak]

Try (attempt) around o (circle) & pm reversed

[mjhall]

Heading should be PRIVATE EYE CROSSWORD NO 716
23d. Member's circle in attempt to get Boris overturned (4,2)

[dannyk13]

Tory MP -o(circle) inside try(attempt) + MP(Member)

[aelmpvw]

i think member is the definition giving tory mp but it's a poor clue