A little national politics over on our diary at RedState [1].
Indications are that the White House is having a bit more to do with gubernatorial primary candidates dropping-off than some might think.
The White House probably didn’t get as involved in NJ and VA because:
1) It was Corzine running for re-election in NJ and
2) Kaine, as head of DNC and the “heart” pick [2] for VP last year, was expected to have the mess cleaned up in his own state
2010 is a different story.