What is interesting about this race is that McCain is doing much better among women than Republicans usually do. To the extent it has been successful, Obama's campaign has done so by appealing to male voters.
I suspect that some of McCain's problems do relate to his history of enthusiastic support of immigration expansion. That means that McCain simply can't recruit a lot of traditional GOP activists (i.e. the kind of folks that helped Pat Buchanan do well in national GOP primaries despite the fact Buchanan had virtually no campaign funding). McCain simply lacks support among any traditional GOP group that is actually capable of mobilizing volunteers in any numbers.
We may be heading towards an election result that isn't just a defeat-but a humiliating defeat. The GOP only has one major national issue the polls say favor a position in which Republicans are more prominent than Democrats—and that is immigration. Strangely, the Republicans that are paying attention to immigration aren't really paying attention to those particular forms of immigration that are most likely to directly impact traditional Republican voters, i.e. H-1b and skills based immigration. Of course, McCain has been among the most vocal supporters of immigration expansion in the GOP. The lesson is simple: don't backpedal on your popular issues.
In the wake of a Republican defeat, I suspect that the leaders will at first attempt to rebuild the part around figures like Sarah Palin and "I love H-1b" Mitt Romney. That will mean Democrats will have a chance to adjust their policies into something resembling sanity.
One interesting thing is that Obama is taking a lot of cues from JFK's playbook. Some commentators talked about how the debate last night reminded them of the Nixon Kennedy debate. Of course that debate didn't come at a time when immigration was a significant issue—and at a time when the US economy still had a postwar boost.
Obama may have the charisma to make some significant changes to traditional Democratic policy. If he really wants to pull the rug out from the Republicans for the next several years, I think he could do so by moderating Democratic positions on immigration and affirmative action-while maintaining traditional Democratic positions on controlling concentration of wealth. Politically this makes sense because the strongest supporters of gender based affirmative action simply aren't supporting Obama strongly in this election. The path here for a successful Obama presidency may be to simply back peddle on his stands that are least popular-and move forward on his stands that have broad support.
It isn't clear to me Obama can follow this political path—but I suspect that Guzzardi is right, that the chance of substantial change in the direction immigration expansion advocates want is also small.