The top prize is the chance to see
Carr perform at a J20 private gig,
DVDs and tickets to Carr's latest stand-up tour will also be up for grabs.
Every entrant will have a Carr joke, or "J20ke", sent to their mobile phone.
The campaign will also include a
viral email featuring stand-up comic Gordon Southern, which can be
tailored to a friend's personal information, making them the butt
of the joke.
Marketing manager Jon Ellis said: "Jimmy Carr is a very popular and instantly recognisable comedian - as well as being very funny - so we are looking forward to a fantastic consumer-focused campaign."