California's Policy on repeating courses?

I don't think that the policy is set by the state. I know that for most nursing programs in my area (San Francisco Bay), if you retook a prerequisite to get a better grade they'll accept it, but only for one course. They won't do it for two, and they definitely won't do it for more than that.

California does not have a policy. You need to research the individual policies of the schools that you are considering applying to. This academic policy is handled at the instutution level, not at the state government level.

The best thing you can do is talk to the schools that you are interested in. The places I looked at would only take one repeat prereq. That may not be the case everywhere though, and you might be able to reach a compromise if you can show them that you're serious and up to the task.

Don't let it stop you from trying. Make some calls and find out if it'll be an issue.