Vice President Kamala Harris has a commanding lead over former President Trump in California heading into the final days of the election, but it is smaller than the victory margin that President Biden enjoyed in the state in 2020, according to a new poll.

Rep. Adam B. Schiff also enjoys a major advantage in his U.S. Senate race against Republican former Dodger All-Star Steve Garvey.

Among likely California voters and those who have already cast ballots, Harris had a 57% to 35% overall lead in California over Trump, which is the same margin as a month ago and hardly changed from her August margin of 59% to 34%, according to the survey by UC Berkeley’s Institute of Governmental Studies, co-sponsored by The Times.

About 5% of voters were undecided, and 3% were backing other candidates.

Harris’ lead is substantially smaller than the margin of victory Biden held in 2020, when he won the state by 29 points — 63.5% to 34.3%.

Some of that decline is due to decreased support among Latino and Asian American voters, who account for more than a third of the state’s electorate, and especially among men in those groups. That trend could have real implications if it holds true in Western swing states with similar Latino communities, said Mark DiCamillo, the poll’s director.

“You’re not seeing the same kind of strong support for the Democratic ticket among Latinos,” he said. “That has implications for Arizona and maybe Nevada as well.”

In the Senate race, Schiff was supported by 55% of respondents, while Garvey was backed by 34%, the poll found. That’s not far off from where the race stood at its start, after a competitive primary campaign, DiCamillo said.

“It’s not really a campaign,” DiCamillo said of the Schiff-Garvey race. “It looks very similar to what we got in late February.”

Schiff, a prominent Trump critic, has been so confident that he has spent much of his time campaigning for other Democrats in swing districts. His campaign declined to comment about the opinion survey. The Garvey campaign did not respond to a request for comment.

Harris and Trump have been barnstorming through swing states. Their campaigns also did not respond to requests for comment.

Anna Kelly, a spokesperson for the Republican National Committee, which is coordinating closely with the Trump campaign, said in a statement to The Times that Trump “will be a president for all Americans, including those in traditionally blue states that Kamala Harris and the Democrats have left behind.”

The latest poll, which was conducted Oct. 22 to 29 in English and Spanish, surveyed 4,341 Californians considered likely to vote or who have already voted.

It comes at an intense moment in the broader presidential race, which is stunningly close across a slate of seven swing states — including Arizona and Nevada, but also Georgia, Michigan, North Carolina, Pennsylvania and Wisconsin.

Pollsters and political observers are watching closely for trends among different demographics of voters, including by race in an election where racism has been featured prominently and where a Black woman tops a major party ticket for the first time. They are also paying close attention to voting differences among men and women — including whether men are moving away from Harris and women are moving toward her, in part because of their discomfort and anger over losing abortion rights.

DiCamillo said California is not directly comparable to other parts of the country. It has a huge Latino population, and is heavily Democratic, he noted. Men in California in particular seem to vote differently than their counterparts in other parts of the country, he said.

Still, the latest Golden State polling does provide a window into a large and diverse part of the country, he said. And its trends, including the decline in Latino and Asian American male support for Harris, could provide insight about the race overall, he said.

Four years ago, California exit polling found about three in four of the state’s Latino and Asian American voters backed Biden. The latest polling put support for Harris at 57% among Latino voters and 56% among Asian American voters — and at just about 50% among Latino and Asian American men.

DiCamillo said California Latino voting patterns are pretty comparable to Latino voting patterns in Arizona and Nevada, if not the east coast, and the decline in support for Harris isn’t a good sign for her in the western swing states.

“When we poll Latinos here in California, we’re getting a pretty good measure,” he said, noting that a large percentage of the nation’s Latino population lives in the state.

Also noteworthy, DiCamillo said, is that Harris’ losses among certain voting segments in California are being offset by gains among white voters, who are supporting Harris at higher levels than they did Biden.

White voters backed Harris over Trump 58% to 36%, the poll found, compared to Biden’s victory margin of 51% to 47% over Trump. College-educated white voters in the state especially favored Harris, backing her 67% to 26% over Trump. Half of white voters in the state who have not graduated college backed Trump, compared to 45% for Harris.

Black voters overwhelmingly supported Harris, though their support took a slight dip from where it stood for Biden — with 77% of California’s Black voters backing Harris, compared to 82% who supported Biden, the poll found.

The poll found that Harris dominates among Democratic voters in the state, and Trump among Republican voters. Harris also dominates in the state’s largest metro areas, including Los Angeles and the Bay Area, while Trump holds wide margins of support in the San Joaquin Valley. Voters in Orange County were roughly split.

Overall, DiCamillo said, the latest polling supports the assumption that Harris will win California — as has every Democratic candidate for president since President George H. W. Bush beat Michael Dukakis in 1988 — and take the state’s whopping 54 electoral votes, the largest electoral prize of any state.

The polling also supports the assumption, he said, that California will continue to be represented in the Senate by a Democrat, with Schiff winning the seat that was long held by the late Sen. Dianne Feinstein.