That sounds like a Macro 1 question, something like IS-LM textbook model...
Eugene Fama argues that "The added debt absorbs savings that would otherwise go to private investment. In the end, despite the existence of idle resources, bailouts and stimulus plans do not add to current resources in use. They just move resources from one use to another." and "The new government debt absorbs private and corporate savings, which means private investment goes down by the same amount."
Basically they start from the national accounting identity S+T=I+G (let's omit open economy for simplicity) and claim that one more dollar to G is one less dollar to I, like if all the rest of the economy, in particular S, were super-fixed.
Brad DeLong and Paul Krugman do not agree. You may say they are keynesians, but still saying that so many things in the economy are fixed seems quite a strong assertion to me. They make two different points one about the money market and one about the goods market.