You may want to check your facts on Smith v. Sununu - I believe it was the other way around (due to Smith bolting the GOP temporarily to run for President w/the Constitution Party).
I found this from National Review by "Googling" Smith vs. Sununu:
{"There are signs President Bush also hopes Sununu will emerge the winner on September 10. Although he issued a blanket endorsement of all Republican incumbents this year, he has made no effort to contain the pro-Sununu overtures going on around him. After adviser Karl Rove attended a fundraiser for Smith in New Hampshire, chief of staff Andy Card went to the state and personally endorsed Sununu. EPA director Christie Whitman attended a May 31 fundraiser for Smith in Boston, but HUD secretary Mel Martinez visited New Hampshire with Sununu in July. Bush's father hosted a New Hampshire fundraiser for Sununu in 2001, and both he and Barbara Bush wrote $1,000 checks to his Senate campaign this June. Even Dan Quayle has jumped into the fray and endorsed Sununu over Smith."}
For fairness and clarity's sake, I post it ALL, but some of this is pure drivel. Bush endorsed all incumbents, including Bob Smith. That was the official WH position. The President himself campaigned for neither man. Funny how this article tried to paint him as being responsible for his parents' and others' support of Sununu. But then, National Review having a need to present everything through a conservative prism, and having journalistic a need to involve the WH in controversy, had to juice up the political angle just a bit.