Traditionally in California (as in most of the rest of the U.S.) most elections are really decided before the primaries take place. Donors and organizations that control volunteers make their choices, if there is any choice other than the incumbent. Primaries just show how well political machines have pushed their candidates. For the most part in California for the past couple of decades this has resulted in very liberal Democrats and very conservative Republicans being elected to the state legislature. None can afford to alienate the machines that elected them. As a result in good times creating California state budgets has been difficult; in recessions, it has been a disaster.
Proposition 14, passed by voters in 2010, is supposed to change that. The two highest vote getters, regardless of party affiliation, will proceed from the primary to the runoff election. This is the same system that has always been used in California for non-partisan offices like school boards and city councils. The framers of Prop 14 hoped that this would allow centrist candidates to emerge and even win. For instance, in a Republican majority districts (most districts are drawn to be heavily biased, a back-scratching agreement between the parties), usually a very conservative Republican candidate backed by the local machine would win the Republican primary under the old system. Even if the Democrats ran a centrist, that Republican would still win the main election. Under Prop 14 a centrist Republican might garner the number 2 spot in the primary, then go on to beat the conservative, machine-supported Republican in the runoff.
All the political parties in California opposed Prop 14, including the Green Party. Now all are working on reasserting their power under the new system. The Republican Party has a pretty good idea for doing that: holding its own internal elections before the primaries. They intend to mail ballots to all Republican voters, and let them decide on who will be the official Republican nominee. That is, who will be backed by party resources. Of course, this will mostly work out to be much like tthe old system because voters choose based on name recognition, and that is based on advertising or outreach by volunteers from the same old sources.
Still, it is better than allowing the party bosses to decide which candidates will be supported by the party.
Whoever the official Republican nominee is for an office, they will still have to run against all the other candidates in the primary, and if they don't place first or second, they will be out of the running.
In my opinion what we really need to give the voters real options is some strengthening of some of the smaller parties, like the Green Party and Libertarians, and a new, centrist party. Call it the California Center Party for now. There are a lot of people in the center, and they want a functioning California government that is not either overly indulgent of the anti-tax crowd or the tax-and-spend crowd.
But no such party has emerged yet.
The GOP Searches for relevance post Proposition 14
California Republican Party
Addenda: facts not so clear about Republican plans: Sparks Fly at California Republican Party [Sacramento Bee, March 19, 2011]