And those No Party Preference voters do have to take action to make their pick for president in March.

[Read more about Californias top-two primary system.]

I asked Sam Mahood, spokesman for the Secretary of States office, to walk me through the process.

Is there an imminent deadline?

Yes and no not really, Mr. Mahood told me.

In December, if you were registered as having no party preference, you were sent a postcard asking if you wanted to vote for president in the March primary, and if so, you were given three ballot options.

You could receive a ballot with either Democratic, American Independent or Libertarian presidential candidates.

Those are the only parties who have chosen to allow No Party Preference voters to participate in their primaries.

If youve already sent yours back with the box checked saying, for example, youd like to vote for a Democratic presidential candidate, youre good, Mr. Mahood said. Youll get to vote for your preferred candidate.

What if Im a No Party Preference voter and did not send back the postcard?

Send it back right away, Mr. Mahood said, if you still have it and you want to vote in one of those three primaries. Otherwise, you may get a ballot without any presidential candidates on it.