smwpe and others,
I think you should take a look at NSPE (National Society of Professional Engineers) and also each of the state chapters of NSPE. This organization has done a lot to promote the engineering profession, and more importantly, be an advocate of professional engineers (rather than the corporation who employs the engineers only).
In the last decade or so, NSPE, at the National level, as well as the state chapters, have had very good success on several issues at the legistlative level.
One example is the importance licensure and fighting all the ways that everyone is trying to call anyone and their brother an engineer. And NSPE has recently successfully defeated attempts, in certain locations, for architects to be the one and only go-to person for all projects. Do architects know which walls should be knocked out when renovating a building?
As someone mentioned before, we all have that inner "engineer" in us, but we'd like for that inner engineer to be licensed if they are going to offer services to the public. (Please don't get me started on how we require every driver on the road to be licensed, every doctor to be licensed, and every hair stylist to be licensed, but somehow it's ok for an engineer not to be licensed). Opps, I just started...
I've always had a feeling that NSPE (or any other engineering organization) would rather stay away from politics, but the reality is: you've got to promote and protect your profession at the legislative level if you want to survive. This means lobbying in Washington DC, and at the state capitol buildings. NSPE has recognized this and has been very active on this front.