No, but there have been highly suspicious circumstances of undocumented Hispanics voting (Loretta Sanchez) in California.
I think Uberroth has to get out and throw his support to McClintock before McClintock has a chance. Then you'd have a horse race and a real choice with Bustamante, Schwartzenegger and McClintock splitting the vote almost equally. Unfortunately, I think Cruz would be mildly favored because you would still have the slavish Unions (teachers, public employees, etc.) all backing the Dem candidate. the only thing that would change that is if the campaigns could link Bustamante definitively with the failing government in the minds of the voters.