The most common and most likely answer to this crossword clue is the 9 plus 7 letter word RETURNING OFFICER
I've seen this crossword clue in The Times
R
E
T
U
R
N
I
N
G
O
F
F
I
C
E
R
Buddy explains!

The straight part
We know that "one announcing results" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one announcing results = returning officer.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.