A couple of things.
Agnosticism is not some middle of the road between theism and atheism. Their belief is that it is not possible to know whether God exists or not. Theists and atheists believe one side of the coin or the other.
Secondly, I don't think evolution is necessarily some telltale sign as to whether you believe in God and/or religion or not. In fact, it is quite misleading. There are many Christians (and those of other faiths, such as Judaism for instance) who believe in evolution, who don't believe a strict, literal interpretation of the Bible. Some even celebrate evolution as a form of intelligent design. Same goes for the Big Bang Theory.
Read this great article for some indication:
http://www.science-spirit.org/printe...article_id=559.
None of these poll choices entirely applies to me, but I will pick True Believer.