The unknown piece in that is the reaction of the economy to each plan. McCain's plan relies on the "hope" that cutting corp taxes will increase business levels and negate what the CBO is projecting as revenue losses.
The Obama plan is pretty much status quo on tax levels to business...so CBO projected losses are a good assumption.
What is absolutely clear is that neither one gets the underlying problem with our economy at this point and both are actually feeding into the problem instead of providing a remedy for it.