Does anybody know, or at least know how to find out, if there is a significant jump in people registering Republican to vote for the good Dr. in the primaries?
I don't know, but there probably isn't much of a jump. For one thing RP is still only at 2% in the polls, and most of them are probably republican already. And another is that they're going to wait until the last minute to re-register.
For California, you must be a republican to vote for Ron Paul.
Who May Register to Vote
# You may register to vote if you meet the following criteria: You are a United States citizen
# You are a resident of California
# You are at least 18 years of age (or will be by the date of the next election)
# You are not in prison or on parole for conviction of a felony
# You have not been judged by a court to be mentally incompetent to register and vote
To register Republican so you can vote in the primary you will need to do a bit of research.
In Texas for example you do not need to register ahead of time, you just show up the day of the primary. In some states you do need to register ahead of time.