When I covered the NGA's summer conference in Philadelphia last year, much of the focus was on the governors who found themselves on all the media "short lists" as potential running mate choices. Gov. Tim Pawlenty (R-Minn.), then the NGA chair, was particularly in focus as a potential McCain pick. Govs. Tim Kaine (D-Va.) and Kathleen Sebelius (D-Kan.), thought to be at the top of Obama's short list, fielded questions all weekend about their relationships with the then-Illinois senator. I even spoke with a then-relatively-unknown governor, who told me: "I really doubt that such a thing would happen. ... I'm just a hockey mom from Alaska, do you really think that it is even in the realm of possibility?"

What a difference a year makes. And it's been a tough year -- a "gubernatorial annis horribilis" for the chief executives of the 50 states, as NPR's Ron Elving points out:

The economy is, of course, the main source of grief for governors of all stripes and in all regions. From Florida to Oregon, state governments are being forced to slash programs, lay off workers and, where possible, raise taxes as well.

...

Many political scientists and other observers continue to view the states as the laboratories of good governance, a source of hope for civic success. But a combination of hard times and bad behavior has battered this belief. And it has done even more to damage the image of the governor as the glamorous executive, the can-do source of solutions.

As a result, the sense that any gathering of the NGA is a casting call for president has faded.