I am impressed that so many people have McCain winning in Washington State. Personally I would think that Huckabee would win after Guiliani and McCain split the moderate vote. Also people need to remember that the Washington GOP can be a hotbed for hardcore conservatives.
Giuliani doesn't seem like the type of moderate that would do very well in Washington and the conservatives would be very, very split between Romney and Huckabee. Eastern Washington has pretty similar politics to where I live and I remember that Romney and Huckabee were about equally popular.