Daily Mail's first objectionable attempt to curry favour (5,9)

I believe the answer is:

charm offensive

I'm a little stuck... Click here to teach me more about this clue!

'attempt to curry favour' is the definition.
I can't tell whether this defines the answer.

'daily mail's first objectionable' is the wordplay.
'daily' becomes 'char' (both can mean a cleaner).
'mail's first' becomes 'm' (1st letter of 'mail').
'objectionable' becomes 'offensive' (similar in meaning).
'char'+'m'+'offensive'='CHARM OFFENSIVE'

Can you help me to learn more?

(Other definitions for charm offensive that I've seen before include "Campaign to gain support and become more popular" , "smarmy campaign" , "PR campaign needed" , "Ingratiating campaign is needed" .)

I've seen this clue in The Times.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.