Among the large amount of academic study of brand management, some of the most interesting is what might be called brand stretching. It’s what John McCain is wisely doing when he’s not sitting in front of the TV watching Clinton and Obama beat each other up.

Profitability of many products is driven both by market share and what category the product occupies. So, for example, whether premium brands or value brands dominate a category impacts how market share relates to profitability. And moving to or stretching into a new category requires careful planning and execution. Some brands have done it very well. Some brands have not. Mercedes did it flawlessly in introducing the C-Class. Jaguar stumbled when it introduced its “lower-class” model.

I’ve been intrigued to see John McCain stand on that famous bridge in Selma, or walk the streets of New Orleans stating the obvious-but-important observation that the current administration failed that city’s citizens (especially, and painfully, minority citizens) following Katrina.

John McCain, obviously, has very strong market share in his principal product category: Republicans. He also enjoys rather strong market share among independents. So, during this time of waiting for the conventions and an opponent, he decides to present perhaps a new picture of himself to categories where he’s not so strong: Democrats, African Americans, etc.

I’m not being cynical. Not at all. John McCain does not strike me as a man who says the President should have been on the ground in New Orleans, not up in a plane flying over looking down, if he doesn’t mean it. He doesn’t strike me as a man who pays tribute to painful memories on that bridge in Selma, if he doesn’t mean it.

And it strikes me that he and his team are doing some very smart brand stretching.