Lists that look most like your current donors can be rented
Having profiled your donor database you will know the types of people you wish to target. You can then request a list of names and addresses that look most like your donors and live in areas you wish to approach.
Benefits
Expand your campaign beyond current donors
Once a person responds their details can be used again in another campaign
Test the effectiveness of different messages and creative on similar types of people
Scale up the campaign using the most effective message and creative combination.