Could the winner of Los Angeles’ mayoral race be decided in the June primary?

The murmurings began shortly after Rick Caruso, a billionaire first-time candidate, began lobbing unprecedented sums of his own money into his campaign.

Speculation grew louder in recent weeks, as Caruso’s spending approached $30 million and several rivals dropped out of the race.

Was Caruso attempting to use unmatched resources to avoid a longer election battle? And could a candidate win outright with more than 50% of the vote while so many others remain on the ballot?

The short answer, based on interviews with local election experts and an analysis of polling data: It is possible, but highly unlikely.

Still, the prospect has some progressives issuing urgent warnings to their followers via social media.

Comedian Adam Conover, in a May 13 message that has been retweeted 10,000 times and screenshot into countless Instagram posts, said Angelenos should be “A LOT more worried” about Caruso’s candidacy — and his chances of securing a majority of the vote in the first round.

“I think that Caruso is gunning to win this way, and I think he has a chance of making it happen,” Conover told his more than 200,000 followers in a follow-up tweet.

Speaking to a reporter on a sun-dappled upstairs patio at the Grove this week, Caruso gave little credence to the rumors.

“The truth is I’m attempting to win and I’m focused on that,” Caruso said, saying he didn’t give the purported 50+1 strategy “a lot of thought.”

Asked whether his mammoth campaign spending is part of a concerted one-and-done primary bid, Caruso said the money was being used to get a message out — a message he characterized as “obviously being well- accepted by the voters.”

Fernando Guerra, director of Loyola Marymount University’s Center for the Study of Los Angeles, had serious doubts about a June victory. With several other candidates still in the race, “I don’t think the numbers are there,” he said.

“But if anybody has the resources to try that play, it would be Rick Caruso,” he said. “So why not try it?”

Politicians at City Hall have a long track record of winning outright in the first round when they are seeking reelection. That was the case in 2017, when Mayor Eric Garcetti won reelection for his second and final term with 81% of the vote in the primary. His predecessor, Mayor Antonio Villaraigosa, did the same eight years earlier.

A first-round triumph during a race for an open mayoral seat would be a different story.

Over the last century, no new mayor has won outright during a primary election. And even with several wild-card factors in this race, experts and political consultants say it’s not likely that we see such an outcome in June.

The battle to occupy the top seat at City Hall has looked like a two-person race between Caruso and Rep. Karen Bass for months. Councilmember Kevin de León, a prominent local politician who has trailed Caruso and Bass as a distant third in recent polling, recently went on TV with an ad narrated by actor Danny Trejo.

De León and his supporters have long posited that Latino voters, who make up a substantial portion of the city’s electorate, will ultimately swing toward De León at the last minute.

A poll of Latino voters from NALEO Educational Fund conducted about a month ago found the largest share of voters were undecided, with leading support roughly split between De León and Caruso and at 17% and 15%, respectively.

“The vast majority of Latinos will be voting on election day,” De León said in an interview. “That’s why we’re working around the clock every day to earn every single vote.”

Other names on the ballot include activist Gina Viola, who’s commanded a small but dedicated following running to the left of Bass, former Metro board member Mel Wilson and former public relations executive Craig Greiwe.

Beyond the mammoth sum of money Caruso has already put into the race, other factors have fueled speculation about the developer taking a shoot-the-moon in June approach.

Two well-known elected officials, Councilmember Joe Buscaino and City Atty. Mike Feuer, dropped out of the race. Buscaino, the first to drop out, endorsed Caruso.

The Los Angeles Police Protective League, which represents LAPD officers and has endorsed Caruso, has put about $4 million into a political action committee aggressively attacking Bass in TV ads. (Election rules stipulate that the outside PAC cannot coordinate with the Caruso campaign.)

John Shallman, a veteran L.A. political consultant who helped lead Feuer’s campaign, thinks Caruso is trying to win in a single round, to avoid the scrutiny that would come during a five-month runoff campaign. But he doubted the effort would succeed.

“He’s a business guy with a lot of baggage, so he wants to strike now and buy this election while it’s relatively cheap and before people have time to vet him,” he said.

Shallman said the prospect of a first-round victory by Caruso was among the factors behind Feuer’s decision to drop out and endorse Bass last week.

“Normally you wait for the losing candidates to endorse you after the primary, because you’re thinking of the general,” said Raphael Sonenshein, a local government expert who runs Cal State L.A.’s Pat Brown Institute for Public Affairs. “But if your hope is to really just knock it out in the primary, this is a good strategy: Spend a ton of money, lock up endorsements, hit really hard. ... It doesn’t mean it’s to the exclusion of trying to win in November.”

Still, getting more than 50% of the vote in a race where nine candidates are still running — and 12 names remain on the ballot — would be an extremely difficult feat. Polling results released by Bass and her supporters only reinforce that idea.

A political action committee promoting Bass provided The Times with results that put Caruso at 37% and Bass at 35% among likely voters. A separate set of survey numbers provided by Bass’ campaign showed her with 34% support among likely voters and Caruso at 32%.

Both polls put Caruso and Bass within the margin of error of each other. By that token, Bass could theoretically also make a play for an unlikely June victory, but her financial resources are far more limited.

Avoiding a second-round, head-to-head matchup with Bass could have advantages for Caruso. When the survey from the pro-Bass PAC narrowed the choice for voters to just Bass and Caruso, Bass took a nearly 10-point lead, drawing support from 48% of likely voters, compared with Caruso’s 39%.

Anna Bahr, a spokesperson for Bass, scoffed at the idea of Caruso winning outright in June, positing that the June election results would likely show Bass — and not her opponent — in first place.

Morgan Miller, the chair of the PAC supporting Bass’ candidacy, saw the landscape quite differently.

“Turnout is everything and right now it’s looking grim,” Miller said, citing the fact that 5% of eligible voters have returned their ballots thus far. “If these trends continue, Rick Caruso could be elected mayor of Los Angeles in June.”

Former City Controller Laura Chick doubted that Caruso could pull off a primary win, pointing to the other politicians in the race. But she said it would make sense for the Bass campaign to use such a scenario to frighten her supporters, which could boost turnout and persuade donors to give — or give more.

“I really think that’s a great fundraising technique” to say Caruso could win in the first round, Chick said. “And I don’t believe it for a second. How can he take it in the primary? I would be totally shocked.”’

Times staff writer Benjamin Oreskes contributed to this report.