Why do you suppose people on the right are so nasty about Arnold? Regardless of his position on issues, whether he is conservative, moderate, or liberal, doesn't he have a right to run?
What is it that they are so upset about? Either he will win or he won't. If he loses, it will mean that either Davis is retained or one of the other candidates wins.
Now if Davis wins, nothing changes. However, Arnold being in the race makes it almost certain that Davis will be recalled.
If Arnold loses to another Republican who is more conservative, then the right wing of the Republicans in California will be vindicated.
But if Arnold wins, Davis is out and those who have spent the last three years screaming about how no moderates have been ignored will have been proven wrong.
And we can't have people like Rush be wrong, now could we?