Kitty follows success with the card to win top prize (3,3,7)
I believe the answer is:
hit the jackpot
'to win top prize' is the definition.
(I've seen this before)
'kitty follows success with the' is the wordplay.
'kitty' becomes 'jackpot' (synonyms).
'follows' says to put letters next to each other.
'success' becomes 'hit' (a hit is a commercial success).
'with' is a charade indicator (letters next to each other).
'hit'+'the'='hitthe'
'jackpot' after 'hitthe' is 'HIT THE JACKPOT'.
'card' is the link.
This may not be correct. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for hit the jackpot that I've seen before include "Win the big prize" , "Win top prize" , "Have a big success or stroke of fortune" , "Achieve lucky success" , "Strike it lucky" .)