This guy thinks that a significant proportion of them might consider voting for a Demcoratic candidate. Some of his "analysis" is based on this poll, described here. Since those who answered the questions in effect "volunteered" for the poll, I don’t find the results credible.
This article captures the lay of the land a bit better, I think, as it describes a certain confusion, but no mass movement in the direction of the Democrats. Yes, the issue portfolio is broader than it might have been a decade ago, but note that the war against radical jihad is up there too.
And Nicholas Kristof is onto something, as George W. Bush has been for years.
Finally, I’d second at least some of the line of argument the good folks at Acton have been making, especially this part:
Now of course there is no one “Christian” set of policies on the best way to help poor or stimulate an economy. Unlike life issues, these are prudential matters and good Christians can disagree. Yet there seems to be a growing tendency among Christians to allow the left to claim the moral high ground with their big government interventionist plans despite the fact that history has shown this to be not only ineffective but harmful.