California has more registered Republicans than any state in the union, but that doesn’t mean any of them will make it to the second round for the US Senate seat.

Six months before the March 5 primary, two Democrats appear likely to face off next year to decide who will replace longtime Democratic Senator Dianne Feinstein, according to a new poll from the UC Berkeley Institute of Governmental Studies, co-sponsored by The Times.

The prospect of former Dodger and Padres legend Steve Garvey entering the race as a high-profile Republican has not disrupted that dynamic, the poll found.

Representative Adam B. Schiff of Burbank and Katie Porter of Irvine are neck and neck, with support of 20% and 17% of likely voters, respectively, the poll found. The two have built significant lead over their other prominent Democratic opponent, Rep. Barbara Lee of Oakland, who sits at 7%.

Garvey, who has not yet announced whether he will run, and Republican businessman James Bradley each also received 7% support in the poll. Attorney Eric Early, a perennial GOP candidate, sits at 5%. About a third of voters surveyed said they had not yet made up their minds.

Under California’s top-two system, the two candidates with the most votes in the primary, regardless of party affiliation, advance to the general election.

The more Republicans there are [in the race]”The less their chances are of getting someone in the top two just because they’re splitting each other’s support,” said Mark DiCamillo, director of the Times-Berkeley poll and a longtime California pollster.

You can change that with a lot of campaigning, but they don’t seem to be as competitive for the top two positions at the moment, he added.

The GOPs Early was favored by 18% of likely voters in a May Times-Berkeley poll, but saw its support plummet over the summer. In that survey, Porter was close behind with 17% support, followed by Schiff at 14% and Lee at 9%.

Garvey was not included in the previous poll but has spent all summer thinking about entering the race, his adviser Andy Gharakhani said. Steve is seriously considering entering this race and speaking directly to voters on the issues they care about most, Gharakhani said.

Despite several months of campaigning, Lee remains less well known than Schiff and Porter, with half of likely voters having no opinion of her. Although she is the only black candidate in the race, she trailed among likely black voters with 16% support, behind Schiff’s 30% and Porter’s 21%.

One factor that could shake up the race is whether Feinstein will be able to complete her term. Beginning in late February, she was hospitalized for a week with shingles. The illness kept her in San Francisco for months. The dozens of Senate votes she missed, including several on judges, led some in her party, including Representative Ro Khanna of Fremont, to call on her to step aside.

Last month, she was hospitalized again after falling at her home in San Francisco.

If Feinstein were to leave before the end of his term, Governor Gavin Newsom would have to name a temporary replacement. After appointing a man to fill Vice President Kamala Harris’s former Senate seat, the governor vowed to elect a black woman if Feinstein’s seat became vacant.

Newsom has not endorsed anyone in the Senate race, but some of Lee’s supporters have said he should nominate her if the seat becomes vacant.

When asked what Newsom should do if Feinstein steps down, 51% of likely voters said the governor should nominate someone willing to run for a full Senate term in the 2024 election.

A quarter of likely voters believe they should nominate someone who is willing to serve as an interim officer and not run for a full term. The rest had no opinion.

Schiff and Porter have remained silent on the matter and simply wish Feinstein the best in her recovery.

The race between Schiff, a former prosecutor first elected to the House of Representatives in 2000, and Porter, a UC Irvine law professor first elected in 2018, threatens to become a generational divide.

Voters over the age of 65 are likely to prefer Schiff over Porter, 29% to 12%, the poll found. Those under 50 prefer Porter: She leads Schiff by 23% to 14% among likely voters aged 30 to 39 and from 27% to 6% among voters aged 18 to 29.

That could pose a problem for Porter: she does best among those who, while likely to vote, often fail to show up during elections. A recent analysis of state voting by the Berkeley Institute of Governmental Studies shows that mainstream voters tend to be white and older than the average Californian. The frequent voters were also disproportionately older than 50 years.

But the fact that the election takes place in a presidential year could mitigate that disadvantage, says Sara Sadhwani, a professor of politics at Pomona College.

One of the things we often see among younger voters is an increase in turnout in a year before a presidential election, she said.

Porter has done a great job during committee hearings, creating viral moments that appeal to younger voters on social media, Sadhwani said. The question, however, is whether these voters will turn up for the March primaries.

Schiff has used his prominent role as former President Trump’s top antagonist to boost his election to the Senate. That seems to be paying off with some Democratic voters. He received additional attention when House Republicans voted to censor Schiff for, in their opinion, going too far in his efforts against Trump, a rebuke Schiff has described as a badge of honor.

It was a chance for Schiff to once again remind California voters of the important role he has played in efforts to save our democracy, Sadhwani said, adding that Republican House Speaker Kevin McCarthy only but had helped amplify with the vote of disapproval.

Schiff is by far the best-known candidate in the field, with only 24% of likely voters having no opinion about him. He received favorable views from 43% of likely voters polled, while 32% had an unfavorable view.

Porter is less well known: 43% of likely voters say they have no opinion of her, 38% say they like her and 19% say they have an unfavorable view of her.

She leads voters in Orange County, where she lives, but Schiff leads in the San Francisco Bay Area. The two are neck and neck in Los Angeles and elsewhere in the state.

The fact that both leading Democrats are from Southern California is a shift from the state’s previous pattern, noted Chris Lehane, chief strategy officer at Haun Ventures, who previously served as an adviser to the governor. Gray Davis and Vice President Al Gore.

Historically, the Democratic primaries have been won by a Democrat in the north over Democrats in the south, Lehane said. I think it’s a fair question whether that’s still the case.

If you think Feinstein first ran 30 years ago, it was a purple state. Now it is a deep blue state. Everything has been nationalized, he added. It seems that the dynamic between Giants and Dodgers is no longer there.

Schiff leads Porter by 31% to 26% among registered Democrats polled. Among likely voters who identify as strong Democrats, he leads her 35% to 27%.

The two are essentially tied to voters registered with no party preference or as members of a smaller party.

The Berkeley Institute survey surveyed 6,030 registered voters in California online in English and Spanish between August 24 and 29, including a weighted subsample of 3,113 likely to vote in the March primary.

Because the survey results are weighted to match census and voter registration benchmarks, margin of error estimates may be inaccurate; However, the results for the likely sample of voters are estimated to have a margin of error of 2.5 percentage points in either direction.