Smith, an ex-Marine, runs a global enterprise of staggering logistical complexity. And McCain has said he'd make a good Defense
But Smith doesn't always back McCain, parting ways recently on a proposal to temporarily lift the federal gas tax.
Said Smith: "I'm an ardent supporter of Senator McCain, but I don't agree with him on everything.... Will it have any major effect on the energy crisis? The answer to that is no."NEXT: Meg Whitman Former CEO, eBay