Certainly there were some Democratic voices who have always been righteous on this issue, and understand it through and through (and aren't simply playing xenophobe cards), voices like Dennis Kucinich, who honestly we cannot say is in the Democratic mainstream.
I was a Kucinich voter in 2004, and I wasn't alone, if you want to be truely entertained look at the resuls of Democrats primaries after the March contents in which Kerry became the effective winner.
Indiana voted in May, year Kerry could only muster something like 70% of the Democratic vote. Many people voted expressively rather than instrumentally, that is they voted for as an expression rather than the actual expectation there candidate would win.
Being in California, you may not see this as much. But in many states of the Midwest, we have a history of getting frustrated with the system and voting for third parties. Like the great Hoosier socialist, Edward Debs, of the Wisconin progressive LaFollette. And I'll give my consent to any government that does not deny a man a living wage-Billy Bragg
Still, Minnesota is arguably trending far less social democratic as the Scandinvian culutral heritage is undermined by assimilation. In other areas of the Great Lakes states what I see most strongly is that with deindustrialization large parts of the working class have been taken up by the idea that there isn't a dime's worth of difference between the two parties. And when debate is suppressed it only serves to validate that view. And I'll give my consent to any government that does not deny a man a living wage-Billy Bragg