What follows is for would-be politics wonks. The importance of a big GOP win on November 2 goes beyond simply getting control of the House of Representatives and quite a few state houses. Because this midterm election coincides with a Census year, there will be redistricting in a number of states, reflecting population shifts within the nation during the last decade.
We speak, of course, of gerrymandering. Political parties that control states where congressional seats are lost or added have undue influence on how new districts are drawn. They can craft electoral districts which will influence legislative political outcomes in their favor for the next decade. Here is an Associated Press article from Yahoo News that considers these issues.