I can't say this often enough when we talk about presidential veepstakes: there are only two people about whom we can confidently say that they know where Barack Obama and John McCain are headed.
And neither of them--the two nominees themselves--is publicly talking.
The sense we in the media get about this is second hand; from the larger pool of each party's political professionals, and from advisers and aides to the candidates. But the aides who know the most talk the least, except right before the decision is announced and some disclosure serves their interests of protecting their candidate from the unexpected.
So take my guesstimates below with a grain of salt. Chances are quite good they've be wrong in some or all respects.
For Obama, I'd expect the vice presidential announcement to come within about 10 days of the August Democratic convention that begins Aug 25. I'd rank his potential VP choices in this order of likelihood: Gov. Tim Kaine of Virginia, Gov. Kathleen Sebelius of Kansas, Sen. Evan Bayh of Indiana, Sen. Joseph Biden of Delaware.
McCain's choice and timing seem more of a wild card; that's because he's behind, and trailing candidates are tempted to risk the unconventional. Still, I'd expect him to wait until just after the Democratic convention ends to make his choice, if for no other reason than to preserve the strategic flexibility that comes with the opportunity to unveil your choice after the other guy does.
I'd rank his choices this way: Former Gov. Tom Ridge of Pennsylvania, Gov. Tim Pawlenty of Minnesota, former Gov. Mitt Romney of Massachusetts and Federal Express chairman Fred Smith. As a political novice, Smith would plainly be the biggest longshot of the bunch, but his combination of military experience (Vietnam) and success building a universally known and respected company offer a roll of the dice that might appeal to McCain's free-wheeling streak.
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