It's way too early to say this. For one thing, the Democrats used to be the party of the rich white racist, and they've pretty well shook that.

But it's not out of the question that we could be seeing the beginning of a Republican permanent destruction. Parties do come and go in the US, if slowly. The Repubs didn't exist until the 1850s.

Factors in favor of Repub destruction
1. They are in a very tight, and shrinking, space. They are becoming the party of the South and Appalachia. At the same time, the Democrats are making incursions into the suburbs.
2. Minority votes are growing; white votes are not.
3. They have no up and comers that are currently popular outside of that self-imposed South/Appalachia political ghetto.
4. Ideologically, they are boxed into an anti-government, socially conservative position that doesn't hold as much power now that there is no external socialist threat (for the anti-government thing) and doesn't represent the increasing openness and tolerance of average Americans outside of Appalachia (on the social conservative thing).

Factors against
1. Come on. We've had two parties since the 1850s. Why should one of them self-destruct now?
2. What's to stop them from changing. The Dems did it during the civil rights movement. Once the GOP finishes post-election moping, why not start moving on some of their policies. The Tories did it.
3. What if Barack Obama is just a really lousy president. I love him and think he'll be great, but failure is always an option. If the Democrats overreach legislatively and Obama is viewed as a failure, all those blue states will be red again in 2012 or 2016.