This GREAT post by Kevin Kelly, author of The Technium blog, landed in my e-mail because I subscribe to Seth Godin's blog. You should read the WHOLE thing, but in case you're short of time - here's the gist.
The LONG TAIL has created a situation where even the smallest artist (read nonprofit) can gain access to fans (donors) cheaply and efficiently. Why? Because inexpensive technologies, like blogs, websites, social networking platforms, online video, podcasts, and e-mail, enables artists (nonprofits) to market (fundraise) for little or no monetary cost.
In other words, if you are a poor and/or new artist (charity) you don't have to wait to get a record deal (big foundation grant) in order to succeed. And you don't have to land on American Idol (get covered in the Times) to become a success. You can simply get online via a blog, Facebook page, YouTube video and slowly but surely find Your True FANS (DONORS).
I like Kelly's thesis so much because, aside from saving us all money, finding and nurturing relationships with a SMALLER number of folks is a much more rewarding way to work. Instead of treating prospective donors as anonymous checkbooks, it gives you the opportunity to have CONVERSATIONS with supporters and develop REAL connections.
That said, "micro-marketing" may not work for all charities. Maybe your advocacy strategy requires a mass market approach, i.e. 1 million signatures to get a bill passed. However, for most of us finding and nurturing 1,000 true donors is probably the best strategy. Try it. What have you got to lose?