I know at least a half dozen people who have told me that if Bush does not start deporting illegal immigrants en masse - and lock down the border by using the military and not just some "fence" that they can easily scale or tunnel under - they will not show up to vote in November. Sure, those nuts are out there.
But they are not strong enough in numbers to make a difference in November. Even so, they will be blunted by moderates and independents who will appreciate reform.