After their wave, the Democrats assumed that the nation had swung to the left and that their policies were now popular. When that proved false, they blamed Republican obstructionism for their failure to pass their agenda. Had they proven to be competent in keeping their promises, the Republicans would be worried about their place as a permanent minority party. Instead they have their chance. They need to provide solid leadership rather than pushing a partisan agenda. If they can do that then it is the Democrats who will worry about being a permanent minority. If they fail as spectacularly as the Democrats did then we will be looking at new swing elections in 2022 and 2024.
So the voters who, in 2006 and 2008, rejected the Republicans because of incompetence, have now rejected the Democrats for the same reason.
Jump forward to the current election and we find that Obama broke all of those promises. His administration is the most opaque, partisan and dictatorial ever. The economy has improved but most of the benefits seem to have gone to the rich. Most of the new job openings are for low-wage jobs Middle class wages have stagnated and millions have left the workforce. Iraq, which seehmed won in 2008, now seems worse than ever and Afghanistan is no linger the "good" war. Obamacare has never been supported by the majority of the population and is currently less popular than ever.
A week after the Republican wave election, I'm not sure that many people on either side really understand what the election was about or the cause of so much voter anger. This can best be understood by contrasting the 2014 election with the 2006 and 2008 Democratic waves.In 2006, the Democrats retook Congress and won many state elections because of President Bush's perceived incompetence. The war in Iraq and the response to Hurricane Katrina were unpopular. By 2008, the financial meltdown was added to the list. Accordingly, voters turned to Obama who promised an open, nonpartisan administration that would fix the economy, clean up the wars, and pass health care reform without an individual mandate.