It'd probably be easier to adjust the current Raffle module to show The List of current names that have joined the raffle in the Raffle Admin window. Place an extra clicky link name like "Show Raffle Entrants" in the Raffle Admin view to update that list so you can boot those that won something previously before you hit the "Show Winner" link.
That how I'd probably do it anyway. But it could be extended a step further. Say for example have a Raffle History in a Table in the database that would record - Who Ran the Raffle, What date/time it was ran, What was Raffled, and Who Won the Item Raffled. Simple 4 colomn table that you could query off of.