The Senate seat opened up on the Coast by Senator Feinstein’s impending retirement would normally present both political parties with an enticing prospect in 2024. Yet the GOP looks likely to be shut out of the race due to California’s primary rules, described by NPR as a “free-for-all.” It’s called a “top two” or “jungle primary,” in which the two top vote-getters of either party advance to the general election. It’s a disaster for Republicans.

The jungle primary was imposed in 2012 after being backed by a Republican, Governor Schwarzenegger, under the delusion that, as a Golden State political scientist, Christian Grose, explains, it would “allow voters who are no-party affiliation to participate in primaries.” The hope, Mr. Grose says, was that it would encourage “moderation or less extremity among candidates who had to run in a general election” and “appeal to voters” of all parties.

Mr. Grose contends the jungle primary has made the state legislature “less polarized than it was before 2012.” He says the solons there “are less extreme.” The Atlantic hails the jungle primary for aggravating both Democrats and Republicans, observing that a “main goal of the change was to reduce the power of the major parties and the insiders that run them.” Yet the jungle primary has largely benefited liberals.

Feature the partisan composition of California’s House delegation. As of 2010 it comprised 34 Democrats and 19 Republicans. In the 2012 elections, the GOP lost four seats. In the most recent House elections, Republicans were down to 12 seats. As for statewide offices like Governor or Attorney General, the GOP occupies none — and hasn’t since the 2006 elections.  Plus, too, the state legislature has been in Democratic hands since the 1990s.

A Republican Senate candidate in 2018, Tom Palzer, laments that the jungle primary “doesn’t reflect representative government.” He notes that “34 candidates ran for the U.S. Senate in 2016” — yet as a result of the primary rules, the “top two candidates were members of the same party” — Democrats, it just so happens. “That’s wrong,” Mr. Palzer says. “The top vote-getter in each party should move on to the general election.” 

In 2018, when Ms. Feinstein most recently ran for re-election, there were 32 candidates in the jungle primary. Once again, the top two candidates were Democrats. There might be a degree of inevitability in this, considering that nearly 47 percent of Coast voters are registered Democrats, compared with just 24 percent signed up as Republicans. So it’s no wonder that top Democrats are salivating at the chance to run for Ms. Feinstein’s open seat.

As our Matthew Rice reports, Congressman Adam Schiff, known for his Ahab-like pursuit of President Trump in two impeachment drives as well as aggressive investigations from his perch as chairman of the House intelligence committee, already announced his candidacy before Ms. Feinstein said she was stepping aside at the end of her term. Congresswoman Barbara Lee is also reportedly eyeing a bid.

Congresswoman Katie Porter, described by Mr. Rice as “an avowed progressive, social media star, and protege of Senator Warren,” has also thrown her hat into the ring. Yet while the liberal press is calling the Senate contest to succeed Ms. Feinstein a “wide open competition,” as the AP puts it, what they mean to say is that the competition will all be within one party — the Democrats. The GOP doesn’t factor into the equation at all.

Despite the harm done to California by unchecked Democratic control — our Scott Norvell notes that the state faces “an exodus of residents” fleeing its high taxes — there looks to be no hope of fixing its rigged primary system. Worse, Senator Schumer has endorsed exporting it across America, suggesting it would “undo tendencies toward default extremism.” It’s more accurate to say it would impose California’s model of one-party rule nationwide.