Ah...I found my own answer about Karl Rove's nickname.
Turd Blossom = a Texanism for a flower that blooms from cattle excrement.
Doug Henwood wrote:
> A collection of Bush's nicknames:
> <http://www.nndb.com/group/750/000091477/>. Looks like a combination of
> a WASP habit and Bush's personal nastiness.
>
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