Am I entirely off-base in thinking that this bears some resemblance to the McCain endgame?
That's exactly what this is. McCain spent months trying to convince the people of Virginia and Ohio that trickle-down economics were going to solve the financial crisis caused by trickle-down economics, only to discover after it was too late that he had blown it and doubled down on a last-ditch effort to snag Pennsylvania.
The difference is that Romney is willing to use racist tactics, but I am skeptical that it will get him the result he needs.