On the results of the survey depend the extent and the type of campaign, we shall wage.
In the above sentence, is we shall wage a reduced version of the relative clause which we shall wage?
On the results of the survey depend the extent and the type of campaign, we shall wage.
In the above sentence, is we shall wage a reduced version of the relative clause which we shall wage?
On the results of the survey depends the extent and the type of campaign [we shall wage].
Yes, it's a relative clause. Since it's an integrated (defining) one, no comma is required, as shown.
It's not a 'reduced' relative as you put it, but a 'bare' relative, the kind where the subordinator "that" is omitted.
A wh relative is also possible, as you mention.
Yes, but I would say that it should be "... the type of campaign*[no comma]* we shall wage." and "we shall wage" is a shortened version of "... the type of campaign that we shall wage." as it seems to be a defining clause.