For 40 years primary elections in California have been colossal exercises in political confusion. Under a cross-filing law adopted in 1913, Republicans and Democrats filed freely in each other's primaries, and the voters could never tell from the ballot which candidate came from what party. As a result, many a candidate said as little as possible about his party affiliation, and won both sides of the primary. Last week Californians went to the polls under a new primary law and set a different pattern.
Under the new law, candidates must be labeled ("Rep." or "Dem.") on all primary ballots. Thus a Republican...