The most common and most likely answer to this crossword clue is the 7 plus 4 letter word MICHAEL GOVE
I've seen this crossword clue in The Guardian
M
I
C
H
A
E
L
G
O
V
E
More clues leading to the result MICHAEL GOVE
Buddy explains!
The straight part
We know that "Leading Tory/: “I have come last in poll, schooling ultimately a fiasco” (7,4)" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case leading tory/: “i have come last in poll, schooling ultimately a fiasco” (7,4) = michael gove.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.