I couldn't agree more. Like the OP, I was accepted to SAIS for this fall with definitely unrepresentative (read: relatively low) GRE and GPA scores. You just need to find the narrative which connects your undergrad work, work experience, and extracurriculars in a coherent way. Send a brief, exploratory note to a professor or two explaining how you read X online about his work and how you're interested in X as well. You might have to prod to get an answer, but you're building a relationship with someone "on the inside", so to speak, and you can begin to get a sense of the personalities you will deal with. My scores nearly did me in - I know from talking with a professor afterwards - so don't assume this means you'll waltz in because your personal statement shines.
However, unlike the OP, I've decided to not go to SAIS. I don't know how much the "significant funding" he received was, but like him I received a fair amount of fellowship money. Keep in mind 70 to 75% of incoming students receive NO funding at all, and second year funding if you didn't get it the first (from what I've heard) is unlikely, barring academic superstardom. 1 year at SAIS is estimated around $58,000, living costs included. I would be in debt to the tune of $60 - 70,000, which is absolute madness for someone committed to work in the nonprofit sector.
So here are two unsolicited points of advice which, like all of the advice on this board, you should take with a huge grain of salt.
-Whether you are a strong or relatively weak candidate, PLEASE LOOK BEYOND the 8 or 10 schools that are mentioned the most on these boards. If you have a strong sense of your interests (which I hope you do, considering you're looking at graduate school?), there are definitely at least some schools outside the usual suspects that you would be equally (or more) happy. Most likely, they would offer better funding and leave you equally prepared for your career.
-Funding matters, more than you'd like to think. I was quite naive about this, but I suspect I'm not alone. I graduated debt free from undergrad, thanks to my dad. Getting into SAIS, especially considering my less than stellar academics, seemed like a dream come true. However, I started crunching the numbers on debt more realistically.Which, I know, I should have done in the beginning.
Many of you work, or want to work, in the nonprofit field. Look at your expected salary upon graduation, think realistically about what you can earn over the course of your career, and then look at your debt load again. Use the loan calculators on FinAid, look at the new public service loan forgiveness program from the gov, and go into it with your eyes open. Does the debt still allow you to take low-paying, but highly satisfying work? If you imagine getting married or having kids down the line, will you have to delay this until you're more financially secure? I know, you worked so hard to get into a school, and it sucks when you have to take into account such mundane realities. But I realized that debt would constrain my options in ways I do not consider pleasant at all.
Some people will casually toss off their expected debt load numbers and expect nothing but glory from their degree. I slowly realized that I didn't want to live with a sling of debt around my neck for the next 10 to 30 years, and am taking another year to work and really look for something more reasonably priced.
Ok, so this turned into a tangential rant, but hey.
The boards should only be a starting point and an occasional reference. Talk to people with similar career interests, with people who are 10 years down the line. One of my favorite people went to SAIS - I only learned recently that his parents paid for the whole thing.