A similar question: why haven't states like Michigan established the Maine/Nebraska congressional district rule when they had Republican trifectas? (Consider that Bush won 10 out of 15 districts in Michigan despite losing statewide).
The most logical answer is that it would be seen as partisan power grab. Still, its precedent in Maine and Nebraska makes it look less so.
There were efforts to do this in North Carolina (by Democrats) and California (by Republicans) in the past four or five years. In both cases it was seen as a power grab and rejected, although it would have backfired in North Carolina had it been implemented.
