If you believe that Exodus is a permanent title to some land, delivered directly by God, you're a Zionist. There are more Zionists in Texas than Israel.
A "Zionist" is somebody who believes that there should be a state of Israel. It does not hinge of believing that Exodus is a land deed.
The only relevance Exodus (and the rest of the Tanakh) has on this discussion is that it proves the historical connection of Jewish people with the land in question, since they have been writing about it for hundreds of years! Even within Exodus (and the rest of the Torah) the composition spans centuries, as there is a long time span between J/E sources on the older end and D/R at the more recent end of the compositional development.