California holds a special election to fill the vacant State Senate seat, 21st district, on March 17. Only one name is on the ballot, Sharon Runner, a Republican. However, six candidates have filed declarations of write-in candidacy. See this story. Three of the write-in candidates are Democrats, one is a Republican, and two are independents. California still has write-ins in primaries, but not in general elections, for state office and Congress.
Very fertile ground for an interesting campaign and excellent example for Top Two with all eyes on the special election.