Committee forming

I am hard at work on my prospectus - the plan for my dissertation - which I have to get approved before I can dig into the dissertation itself. One small difficulty - putting a committee together that will get me through this process. I had a stroke of good luck today when one professor agreed to "join the crew." My choice for committee member #2 declined, and my other options in this category aren't that great, so I'm in a bit of a bind here. I think some groveling is in order, and if that doesn't work, some creative thinking will have to get me through.