Bump from the grave, but ktessitore if you are still wondering about this, you may have been misunderstood above. Are you asking: can you have a range of numbers that will always be accepted as valid coupon codes?
If yes: Sure you could. But it's definitely going to be a workaround. I'd "create" the coupons one-by-one, but using a script to loop through and add every number as a new row in the "coupons" table.
I'm currently using this method, but for a different purpose... generating random one-time use coupon codes to be distributed through e-mail marketing. Sure, I have 1000+ coupons listed in coupon admin but it doesn't seem to be hurting anything. The only drawback so far is there is no good way to see a summary of how many coupons have been used, what % of sales use coupons, how many active coupons are still unclaimed, etc.