You could try a quiz night too. Also a bit of craic and it makes money too. In my experience not as much as the race night (where you can whip them up to spend more money) but still easy and fun to arrange and partake in. You could also sell sandwiches, crisps, tea/coffee at both.
Another thing we used to do was to approach local businesses for a 'spot prize'. Say the local Supervalu for a tenners worth of pork chops, or the bookshop for a gift voucher, and then sell raffle tickets for,say, 50 cent each at the start of the event. We'd then have a draw every so often over the course of the evening and we'd always loudly announce who was so generous as to have provided the prize to give them a bit of publicity
As I think about it another thing we did was to print a 'race-card' for the race nights and get local businesses to 'sponsor' a race. It might only have been 20 extra pounds (in those days) to the winner but sure it pulled the bets in.
Good luck with it! You'll need a bit of a brass neck to go out and about with your begging bowl but it'll be well worth doing so.