LOS ANGELES — Republican former baseball star Steve Garvey calls himself a “conservative moderate” who shouldn't be buttonholed into conventional political labels, a self-styled description that provides a window into how he hopes to win over independents and soft Democratic voters in his longshot Senate campaign against Democratic Rep. Adam Schiff.

A Republican hasn't won a Senate race in California since 1988, and GOP candidates running conventional statewide campaigns have a long record of Election Day misery in the heavily Democratic state.

Garvey's campaign has already benefitted from his splash of celebrity appeal — he's a former MVP and perennial All-Star who played for the Los Angeles Dodgers and the San Diego Padres. In a presidential election year, the campaign plans to emphasize that he is not a rigid devotee of former President Donald Trump and his Make America Great Again movement, even though Garvey has voted for Trump twice and hasn't ruled out doing so again.

At the same time, the campaign will look to target persuadable, middle-ground voters grown weary of the state's left-leaning politics and homeless crisis, as well as rising gas prices, crime rates and housing costs. On Tuesday night, Garvey urged those disillusioned by the state's challenges to “come join us.”

“We don't have a single endorsement on the website — that's intentional. It's a Steve Garvey campaign,” said campaign communications director Matt Shupe.

“He's never been this partisan guy,” Shupe added, noting that since the start of his campaign Garvey has said he would seek votes across party lines. “We have an open field to define him politically. Adam Schiff does not.”

Given California's prominent Democratic tilt, the strategy that is only beginning to take shape is a gamble at best. And presidential election years typically see elevated Democratic turnout in the state, an additional challenge for any Republican candidate. Meanwhile, Garvey needs to quickly accelerate his fundraising if he hopes to reach potentially millions of voters with texts, digital ads and other costly communication.

He benefitted in the primary from millions of dollars in ads financed by Schiff and his supporters that attacked Garvey as “too conservative,” which indirectly lifted his profile with Republicans and right-leaning voters.

Schiff and Garvey easily outdistanced their two main rivals Tuesday, Democratic Reps. Katie Porter and Barbara Lee. Garvey notched his spot on the fall ballot by positioning himself as an outsider running against entrenched Washington insiders.

“You can't run a traditional partisan campaign,” said Ron Nehring, a former state Republican Party chairman. “He cannot take a hyperpartisan or strident ideological approach.”

Republicans account for only about 1-in-4 voters in the state, so Garvey will need to look to other groups to build a competitive coalition. Those could be built around issues, such as drug abuse or the high cost of living, or geography, such as with farmers in the state's Central Valley.

“A Republican has to build a majority in California not by party registration, but by going after one group after another,” Nehring said. He even suggested Garvey reach out to members of Porter's campaign who might be angry with Schiff to try to lure support: “Most of them will say no, but a handful of them may say yes,” he added.

The strategy to ferret out dormant, potential supporters bears resemblance to a sprawling turnout operation mounted by billionaire Republican-turned-Democrat Rick Caruso in Los Angeles' 2022 mayoral race. He deployed hundreds of paid canvassers to reach out to undecided Latinos, Asians and independents. He lost to Bass by just under 10 points.

On Tuesday, Garvey expressed optimism about the campaign to come for the seat once occupied by the late Sen. Dianne Feinstein. It’s a rare opportunity for the GOP to compete in a marquee statewide race in this Democratic stronghold.

“They say in the general election that we’re going to strike out,” Garvey, a first-time candidate, said of his doubters. “Know this: It ain’t over ’til it’s over.”

Garvey's low-key campaign and scant public appearances worked for him in the primary, but voters will be expecting more in a general election. While California showed signs of a possible shift to the political right — San Francisco voters showed strong support for a pair of ballot measures that expand police powers and compel treatment for adult welfare recipients who use illegal drugs — Garvey remains a long shot.

He will also be on the ballot with a GOP presidential ticket likely headed by Trump, who is widely unpopular in California outside his loyal base.

“You can’t sit out a campaign and expect to have any shot in the general election if you are in the minority party in this state,” said Thad Kousser, a political science professor at the University of California, San Diego.

California puts all candidates, regardless of party, on the same primary ballot and the two who get the most votes advance to the general election.

Schiff enters the race as favorite, but he has challenges of his own. His victory party was marred by raucous protesters who shouted “Free Palestine” and “Cease-fire now,” forcing the congressman to attempt to speak over them as they continued bellowing. Schiff took several pauses, and he appeared to hurry his remarks.

Schiff, who has been outspoken in support of Israel’s right to defend itself, shifted Tuesday and endorsed the Biden administration’s call for a Gaza cease-fire as part of a broader agreement that would include the release of hostages. “My position is the same as the administration,” Schiff said.

Others see little chance for Garvey to stage a surprise.

Republican consultant Rob Stutzman said he didn't see Garvey overcoming the party's math problem in California — Republicans are outnumbered by registered Democrats by about 2-to-1. A Republican hasn't won a statewide race for any office in California since 2006.

“This is about national politics. If a Republican wins statewide again in California, it's not going to be U.S. Senate,” Stutzman said.

Former Republican congressman Doug Ose was blunt: “I think Adam Schiff is the next senator from the state of California."