Adwords Keyword Matching Questions

I'm thinking about doing some PPC marketing in Adwords. I have a question about Google's keyword matching rules. First, some background:

Let's say I go into my Adwords account and get traffic estimates for "blue tennis shoes" (phrase match) and [blue tennis shoes] (exact match). In both cases, Google reports (a) a $0.05 bid would gain me top spot and (b) I could expect very little traffic for my chosen keywords.

Next, assume that I can confirm through a tool like inventory.overture.com that people are searching on the exact phrase "blue tennis shoes". If people are searching on those keywords at Overture, I can only assume they're doing so in greater numbers at Google.

Finally, assume that when I search Google for "blue tennis shoes", I see lots of Adwords ads. Since Google reports no competition for the full phrase, I can only assume that there are bidders for a shorter phrase like "tennis shoes" or even a broad match like: tennis shoes.

Now, given all of the above, here is my question: If I bid on "blue tennis shoes" and someone searches on "blue tennis shoes", is it possible that my ad will "slip in" at a low CPC rate of $.05 even though there might be lots of advertisers willing to bid much more for "tennis shoes"?