Well, jsiefert, your defensive response would make me check out the validity of your fundraising partner even more, if I were in any postion to contribute. Still, I thought that the point of these things is to get people in your community to sponsor you, not to make it a donation spam campaign, but, I could be mistaken.....
Now, what I was talking about was the common practice of professional fundraising taking high commissions, not the illegal practice of 'skimming' that you brought up, partly due to my poor choice of words. What I should've said was "How much are they taking off the top for administrative costs". But, since you did, let's continue in that direction....
Often, in charity scams (or near-scams), there is a group that has a name which sounds similar to a more well-known and honest charity. The American Cancer Society, as an example, has been confused with several groups having names such as "the National Cancer Society", "the American Cancer Foundation", etc. Some of these groups turn out to be less than what they seem to be, and many people believe they are contributing to the well-known charity.
I would always be wary of any solicitation for funds from somebody who solicits online. While this particular solicitation seems to be honest, with all the internet scams going on, do you really want to take the chance?