In California, Senate Battle Has the Most Intrigue

California is a big part of Super Tuesday, but don’t expect a big turnout in the state.

With little drama in the presidential primaries, voters have been slow to turn in their mail ballots so far, and lackluster participation is expected for this election. Out of more than 22 million mail ballots issued to registered voters in early February, only about 16 percent were returned by mid-Tuesday.

“Turnout is probably going to be a record low for a presidential primary in California,” said Paul Mitchell, a Democratic political consultant and political data expert. He predicted that less than a third of registered voters would cast ballots in California.

If that forecast holds true, an electorate that is older, whiter and more conservative than usual would make a number of consequential decisions. Among them:

Who will succeed Feinstein?

After Senator Dianne Feinstein died in September, Gov. Gavin Newsom quickly filled the vacancy by appointing Laphonza Butler, then the president of the political action committee Emily’s List. But she is not running to keep the seat.

The subsequent open primary has drawn a crowd of aspiring successors. For months, the clear front-runner, based on polls and fund-raising, has been Representative Adam Schiff, 63, a Democrat from Burbank who served as the lead prosecutor in Mr. Trump’s first impeachment trial.

Locked in a tight race for second place are Representative Katie Porter, 50, an Orange County Democrat and former law professor known for her takedowns of powerful leaders during congressional hearings; and Steve Garvey, 75, a former first baseman for the Los Angeles Dodgers and the San Diego Padres. He is the only Republican among the leading contenders for the runoff.

Representative Barbara Lee, 77, a progressive Democrat from Oakland, has polled consistently in fourth place.

Under California’s “jungle” primary rules, the top two candidates in Tuesday’s contest will advance to a runoff in November, regardless of party. In two prior Senate elections in California, two Democrats have emerged from the primary for an intraparty battle in the general election.

Ms. Porter, a progressive, is hoping for such an outcome, but recent polls suggest that such a contest is less likely to happen. This year, Mr. Garvey’s name recognition has helped consolidate Republicans behind his campaign. So has Mr. Schiff’s advertising strategy.

If Mr. Garvey prevails, and some analysts say he could conceivably place first given the split Democratic vote and low turnout, Mr. Schiff is expected to ride California’s electoral math to a November victory in the heavily Democratic state.

How will the House battlegrounds shake out?

California is dominated by Democratic voters, and the party currently has a 40-11 advantage, with one vacancy, in the state’s congressional delegation. But Democrats believe they can win even more seats this fall, hoping for a “blue wave” like the one they enjoyed in 2018.

A deep red and often-underestimated vein of conservatism runs from the rural north through the agricultural Central Valley and into the Southern California suburbs. In 2022, voters in those congressional districts helped Republicans win control of the House by a razor-thin margin. The question this year is whether the G.O.P. can defend its California battleground districts and maintain its overall edge in Washington.

Tuesday will offer the first hint at an answer. In one Central Valley district, Republicans could secure a battleground seat thanks to an intraparty Democratic fight that could lock the Democrats out of the general election.

Has California cooled on liberal values?

Governor Newsom, a Democrat, proudly trumpets California’s liberal policies, like progressive taxation, social inclusion and abortion rights. But a constellation of local races and ballot measures will test just how liberal California is.

In San Francisco, a local ballot measure would require recipients of county aid to be screened if they are suspected of drug addiction, and condition their benefits on enrollment in a treatment program.

In Los Angeles, nearly a dozen contenders are challenging the progressive district attorney, George Gascón, who was elected with a wave of liberal prosecutors after nationwide protests against police brutality in 2020.

At the other end of the political spectrum, voters in several conservative enclaves will decide whether right-wing Republicans are pursuing local government changes that go too far.

In Orange County, Huntington Beach voters will weigh in on contentious ballot measures championed by a conservative Republican majority on the City Council. This year’s ballot asks voters to effectively ban the flying of Pride flags at City Hall and to require voter IDs at the polls and the monitoring of ballot drop-off boxes.

In Shasta County, voters will reassess the chaotic tenure of a conservative Republican bloc that took over the five-member Board of Supervisors during the pandemic. Voters will decide the fate of three supervisors this year and consider two measures that would amplify the conservative majority’s influence.