The left column shows something I posted a few weeks ago: maps of the states that we estimated were won by McCain and Obama among different categories of family income (as reported in the Pew Research pre-election polls). The maps in the right column show our estimates for non-Hispanic whites alone.
Unsurprisingly, McCain did better among whites than among all voters. In a refrain already familiar to regular readers, I decline to offer explanation or interpretation. There's been enough discussion of the white vote that I think it's a useful contribution to present these (slightly processed) data and give you more information to help you make your own conclusions.
See here for more details on what we did.