Via Ben Smith in Politico.com:
A new Gallup analysis reveals that — at this heated moment — significant amounts of Democratic primary voters say they would take McCain in the general if their preferred candidate doesn’t get the nomination: Clinton supporters appear to be somewhat more reactive than Obama supporters. Twenty-eight percent of the former indicate that if Clinton is not the nominee — and Obama is — they would support McCain. That compares to 19 percent of Obama supporters who would support McCain if Obama is not the nominee — and Clinton is.How about it, Hillerites and Obamatons? If your candidate doesn't get the nom, will you go McCain?
It is unknown how many Democrats would actually carry through and vote for a Republican next fall if their preferred candidate does not become the Democratic nominee. The Democratic campaign is in the heat of battle at the moment, but by November, there will have been several months of attempts to build party unity around the eventual nominee — and a focus on reasons why the Republican nominee needs to be defeated.