This started out as a comment on Yoss' excellent post [
http://www.dailykos.com/...] on the sunset of conservatism, but then I thought "just make it a diary, dude".
So what is it that conservatives conserve, and what does that have to do with immigration?
Answer (with a nod to George Lakoff): conservatives conserve a rigid social ranking system. The conservative appeal even among the working class derives from the fact that almost everyone is ranked above someone else, and would like to preserve that advantage. The conservative boost over the last couple of decades can be related to two main influences. The first is the widely perceived disruption of the "traditional" ranking system represented by domestic social movements like civil rights and feminism. The second is the erosion of America's post-WW2 moment of dominance as domestic oil production peaked, Europe and Japan re-built, and large sections of the third world emerged into modernity for the first time.
Of course, almost everyone is also ranked lower than someone else. For individuals or social groups who are neither at the top nor at the bottom, a rational calculation of whether to support conservatism would weigh the advantages of preserving one's superior position compared to some, against the disadvantages of being stuck in an inferior position compared to others.
This model predicts that white males, who as a group are high-ranked, will tend to vote conservative. Feminists and environmentalists, champions of groups that suffer injustice inflicted from above, will be progressive. African-Americans, perpetually assigned lowest-rank status as a group, will be the least politically conservative of all. Check, check, and check. QED.
When people see that they are more threatened by exploitation from above than by erosion of privilege from below, they will turn away from conservatism. After six years of unchallenged BushCo dominance, almost everyone is significantly worse off. Tax breaks overwhelmingly favored the top 1%; income growth has occurred only in the top 10%; while most feel less job, health, & retirement security; most are deeper in debt; etc. As Yoss shows, when granted free rein, conservatism has failed miserably. By rights, this should absolutely nail the case for massive conservative defeat in the fall.
But Republicans can still win, for example by making immigration a centerpiece of this year's rage-and-panic-inspiring program of deliberate emotional manipulation... er, I mean, dignified debate about our fundamental values as a nation. The image of a great tide of Latino immigrants swamping traditional white security is powerful, and the counter-narrative-- that brown and white alike are victims of the myopia and greed of corporatism and the super-elite-- is not yet well established.
Many Democrats have been trying to run on the "competence" issue. Though they have a great point there, it is not a strong message and does not deserve a featured spot in their campaign. Competence is about whether you are doing things right; Republicans can counter by claiming that (competent or not) they and not the Dems will do the right thing. And the "right thing" in their book will be coming down hard on those low-ranking Latinos who are undermining the position of the Average White Guy. They will try to activate in voters' minds the frame of the threat from below.
Democrats will have difficulty with this strategy until they are willing to affirm actual progressive principles. Just say it: We will reduce wealth inequality. We will increase the minimum wage and ask the rich to contribute a fair share. We will see that regular folks are doing OK, before allocating vast wealth to the favored few. We will look forward to the challenges ahead (global warming, energy independence) rather than back at the way things used to be. We will act in the common good, and that will be good for us, the voters of America, because we are the common people.