Everywhere is a bellwether in American politics these days. And every race allegedly tells you much of what might happen in the midterm elections on Nov. 6.

In California, that just may be true in today’s primaries.

The Republican Party remains a sad-sack affair statewide in the country’s most populous state.

But it does currently hold potentially the critical balance that could keep the House for the GOP or swing it to the Nancy Pelosi crowd. She only needs 23 more House seats to regain the Speaker’s gavel from retiring Paul Ryan.

In California, the GOP presently holds seven seats in House districts that what’s-her-name Bill’s wife carried. Playing on anti-Trump fervor , her party is spending millions to take them back.

But there’s a problem. California has what’s called a jungle primary, meaning the top two primary vote-getters, regardless of party, advance to the main November contest.

Democrats came up with that, counting on so many of the surplus of Democrats turning out that GOP candidates would place third or below.

That may well happen in the U.S. Senate race where Dianne Feinstein would like a sixth term, so much so that she donated $5 million of her $174,000-a-year salary to the reelection campaign. Never mind the dark hair, she turns 85 this month. Many Dems feel like she’s had her shot.

Also, when she went to Washington in 1992, the ex-San Francisco mayor was a real liberal. Today, she looks more centrist, which has drawn out the liberal Bernie Sanders crowd to reenact the 2016 party split and support liberal state senator, Kevin de Leon.

The state committee even denied its endorsement to Feinstein despite her seniority. That likely leaves fall voters with a choice between Democrats.

In the governor’s race to succeed Jerry Brown, there are only 27 (!!) candidates. Another liberal San Francisco ex-mayor Gavin Newsom, now lieutenant governor, leads all polls. The question is who must face him.

Many thought it would be another Democrat, ex-LA Mayor Antonio Villaraigosa. But according to recent reported polls, President Trump’s endorsement of Republican attorney John Cox last month has pushed him into second place.

Here’s the real skinny on that race: No matter what, Cox would be a clear underdog against Newsom and the state unions.

But the Republican hope is his struggle would draw otherwise hopeless GOP voters to the polls to hold those contested House seats and keep the House majority and give the Speaker’s gavel to Bakersfield’s Kevin McCarthy, who pushed the Trump endorsement. The circle of life.

Now, back to the House. So tempting were races in this tumultuous Trump era that a surfeit of Democrats has flooded some contests, meaning they could split that party vote and leave two Republicans on top to duke in out Nov. 6. Karma.

That could happen, for instance, in Dana Rohrabacher’s Orange County district where two strong Democrats — scientist Hans Keirstead and businessman Harley Rouda — are playing out the now-familiar Sanders-Clinton party split.

That could leave second place open to fellow Republican Scott Baugh. A Rohrabacher-Baugh race would guarantee the GOP holds that seat either way.