I think they will lose the debate as they are being dishonest. They argue evolution is only a theory and it has unexplained questions...well all theories have holes in them.

I would point out that "Intelligent Design" is only a theory with holes a mile wide in it. First question is who was the intelligence behind the design? Maybe God? Aren't they just dressing religion in scientific clothing then?

We therefore should just ask for evidence of the existence of the Intelligence. Circular arguments don't count. That is to say ID can not be used as evidence of the existence of an intelligent designer.