This has a very real world counterpart in my opinion.
Look at the Iraq war, USA has the numbers and tech, but they can't defeat Al Quaeda, I mean they can take down some leaders but you can't really "beat" a fragmented group like that.
In some ways you could look at the superior numbers and advantages of the Dominon the same way, but the Hirogen are nomadic, scattered, and the way they operate kind of makes full scale war a non starter. Despite being "hunters" I have no doubt they would be willing to wait in the dark before snaring their "prey".
Al Quaeda has no chance whatsoever of bringing down USA. It can 'wait in the dark' all it wants.
USA, on the other hand, has fragmented it, decapitated it, etc.
One may fail to capture/kill every last member of such dispersed groups, but one can bring them down to the point of near-irrelevancy.
Stalemate? Not even close.