I agree with Moe Lane, http://www.redstate.com/moe_lane/2010/07/11/microcosm-of-the-conservativeliberal-2010-strategy/
and Ace of Spades, except that I see a longer term danger: that the Tea Party or Constitutional Conservative movement will achieve some of its objectives, reduction of the Democrat Party to (temporary) minority status, balanced budgets, prosperity, sane foreign policy, etc., and will become complacent.
That there will not be the same fire. That the People will not be persuaded that freedom can never be secure while progressivism remains firmly rooted in the schools, the unions, the courts, the foundations, the media, and elsewhere.
So that the cancer goes underground, but continues to grow and thrive until, perhaps in response to some perceived crisis, it bursts forth again to power, stronger than ever.
Still, I wish this were a worst case scenarion.