The most common and most likely answer to this crossword clue is the 6 plus 5 letter word BALLOT PAPER
I've seen this crossword clue in The Guardian
B
A
L
L
O
T
P
A
P
E
R
More clues leading to the result BALLOT PAPER
Buddy explains!

The straight part
We know that "One may be spoilt for choice in an election" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one may be spoilt for choice in an election = ballot paper.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.