You want a raise at your company. The biggest obstacle to overcome is that you need to actually go ask for one. Now there are some other factors that may increase success.
Work on some challenging tasks. It is best if they bring in a bunch of revenue. Make sure you take credit for the results. Emphasize the benefit to the company (this is easy if the benefit is that the company made a boatload of cash).
When you ask for more money, don't tie the request for the great job you already did. Talk about what further great deeds you will do. Couple this with a plan to increase your duties.
Before you head in for that raise, have a plan for what you will do if you get denied. Read up on a lot of books on successful negotiation. They will tell you about this. Finally be prepared to switch companies, and maybe even move to a new city.