I think that Charles Krauthammer has it about right. A few snippets:
[T]he great Democratic wave of 2006 is nothing remotely like the great structural change some are trumpeting. It was an event-driven election that produced the shift of power one would expect when a finely balanced electorate swings mildly one way or the other.
This is not realignment. As has been the case for decades, American politics continues to be fought between the 40-yard lines. The Europeans fight goal line to goal line, from socialist left to the ultranationalist right. On the American political spectrum, these extremes are negligible. American elections are fought on much narrower ideological grounds. In this election, the Democrats carried the ball from their own 45-yard line to the Republican 45-yard line.
[B]oth parties have moved to the right. The Republicans have shed the last vestiges of their centrist past, the Rockefeller Republican. And the Democrats have widened their tent to bring in a new crop of blue-dog conservatives.
The public’s views on what we ought to do with the war remain mixed, as do its general ideological inclinations. What happened on Tuesday? The electorate threw the bums out in disgust with corruption and in deep dissatisfaction with current Iraq policy. Reading much more into this election is a symptom of either Republican depression or Democratic wishful thinking.
Read the whole thing.