There has been a dramatic shift over the past 4 years. There are many reasons but most of all, the GOP's shallow, unsubstantial, talking-points-heavy style of governing has seriously soured the public against them.
Gallup has a new poll about the "State of States": about how each state is doing in reference to party affiliation. Looking at the map to show how red/blue states are, the GOP is up the proverbial poop creek with a paddle. The map above shows those trends. It seems the GOP has only about 4 solid states left. Compare the blue to red. Wow!!
GOP had better stop alienating large portions of the population and start trying to become part of our world. The only problem is, they are totally beholden to their base. Which runs directly contrary to the way the majority of our society is trending.
One possible explanation as to why this won't change anytime soon was at Dailykos. The bigger problem the GOP faces is that the moderates repubs have lost their seats (in both house and senate). This leaves only wingnuts. Wingnuts, too fearful of losing their primary to another more crazier wingnut has no inclination to vote on Dem bills when the vote will be later used as a bludgeon during their primary.
Basically, they're stuck.