As an example of what I mean, students who are attending university are generally having their tuition and living expenses paid by the welfare state in the Scandinavian and Germanic countries. And then the government has special funds for the "hobby" clubs that these students join. To me, that is government funding. The Linux kernel itself was government funded in just such a way.
Then look at the various Debian Developers who work on other projects that are government funded, that tie into their Debian work. Andrei Schuldei comes to mind. Sure, they aren't funding him to work directly on Debian... or are they? It ends up amounting to that, since his product is directly based on Debian. In fact, his distribution is even included in Debian, last time I installed it.
Next, look at the corporate sponsors of Debian. It shouldn't be hard. They are quite big and well known.