I'll have a go at parsing, although I suspect that there's something not quite right about the clue as given.
Cable, perhaps = Vince Cable, leader of Liberal Democrats.
left = l
I ace(?) should it be: in the same place? Which could have been 'ibidem', Latin for 'in the same place'. If you 'pick out' the second I, you get 'ib dem'.
Add the first 'l' and you get Lib Dem.
thank you very much captain and bookbinder, it looks as if badrosebud missed some of the clue, it was really nagging at me. i don't have the paper so icould not see the clue. thanks for putting me out of my misery, very kind of you both