House Coalitions: A form of multi-party government?

My thoughts on the value of a multi-party system are in the post immediately preceding this one. However, an interesting question remains...

Can coalitions be thought of functioning as a "third party?"

For some information on coalitions, check yellow dog democrat history, including some humorous descriptions of different flavors of dems, as well as the Blue Dog Coalition official page and wiki article. It might be fun to check out a direct comparison as well.

I think the simplest answer to my question is "no, because coalitions are too small and too unknown to have the required effects." Coalitions don't seem to receive much special media attention, nor do citizens generally describe themselves in terms of coalitions.

Well, I will. I think I could, maybe, be a considered a sort-of-blue-dog-dem. How's that for straddling the fence?

Anyone know of similar republican coalitions?