If California is the political fundraising powerhouse of the nation, Silicon Valley has grown into one of the increasingly dominant forces of campaign cash. And while Northern California tech entrepreneurs overwhelmingly support Democratic candidates, a small but powerful group of defectors has moved rightward in recent years.

A gathering of tech’s conservative cohort enjoyed a visit from former President Trump on Thursday evening at a tony fundraiser held at venture capitalist David Sacks’ San Francisco home. The estate, nestled on Billionaires’ Row in Pacific Heights, welcomed about 80 elites to the sold-out event. Cost of admission: up to $300,000 per person and $500,000 per couple, according to an invitation obtained by The Times.

“It was a couple hours of high-quality networking in a very beautiful private home,” said Harmeet Dhillon, California’s Republican national committeewoman and a San Francisco-based attorney who acts as an official legal surrogate for the Trump campaign. “The seats were all filled. It was totally packed.”

The gathering raised $12 million, Dhillon added.

Across the country, tech leaders and employees have poured millions into politics. People who work in the communications and electronics sector, which includes technology companies, have given $18.1 million to Biden and groups supporting his campaign, and $1.4 million to Trump and organizations backing his effort this year, according to campaign finance data released May 21 by the Federal Election Commission.

The analysis of the contributions was conducted by Open Secrets, a nonpartisan group that tracks electoral finances. The total donated to candidate committees and outside groups supporting the campaigns amounted to $25.8 million, with 71.7% going to Democrats and 22.1% to Republicans.

In Silicon Valley itself — the geographic area that is considered the hub of the tech industry and includes San Jose, Menlo Park, Palo Alto, Mountain View, Cupertino, Santa Clara, Redwood City and Sunnyvale — about 3% of donors who gave to a Democratic nominee in 2016 or 2020 donated to Trump in the following cycle, a Times analysis of FEC data found. While many tech leaders and workers live in these cities, many other residents of this region do not work in the industry.

“Silicon Valley and the Bay Area are the beating heart of the global innovation ecosystem. Given the region’s economic dynamism, as well is its cultural, technological and social impact, it should come as no surprise that more candidates are engaging with our business leaders,” Ahmad Thomas, chief executive of the Silicon Valley Leadership Group, said in a statement. “That’s part of the reason why our region will continue to be a political powerhouse, helping to set a national agenda that supports innovation, entrepreneurship and growth.”

While a sliver of the population is growing attracted to Trump’s friendliness toward emerging technologies such as crypto, Silicon Valley remains reliably Democratic. The region’s tech world is known for its penchant for disruption, with a historic libertarian streak.

“Obviously there’s been some defection, but the reality is the vast majority are still supporting the president,” said Rep. Ro Khanna (D-Fremont), who represents Silicon Valley in Congress.

On Wednesday, Vice President Kamala Harris attended a fundraiser in Oakland Hills before appearing before a crowd of about 100 in San Francisco. During a 13-minute speech, she called for a cease-fire in the Israel-Hamas war, and for Hamas to return the remaining hostages to Israel.

Her remarks did not satisfy the crowd of protesters outside the venue, who shouted “Shame on you!” as Harris arrived.

Khanna recently convened 100 tech leaders for a retreat in Napa to inspire them to stick with the Biden administration.

“Democrats need to have a clear vision on celebrating entrepreneurship,” Khanna said. “Yes, there needs to be guardrails and smart regulation, but we need to be for innovation. We need to be for entrepreneurship. We need to be for wealth generation. We need to be future oriented.”

But for some Silicon Valley tech executives, being future-oriented means campaigning for Trump.

In the latest episode of their podcast, “All-In,” Sacks and his co-host for the fundraiser, Chamath Palihapitiya, emphasized that they had previously hosted fundraisers for independent presidential candidate Robert F. Kennedy Jr. and Trump’s former Republican opponent Vivek Ramaswamy.

Palihapitiya, a self-described “apolitical” person, said he had donated to Democrats in the past, even as he joined Sacks for the Trump fundraiser Thursday. The two podcasters joked about the flak their other two co-hosts, Jason Calacanis and David Friedberg, were getting for associating with Trump supporters.

“I think you guys are getting more blowback, and that’s an indication of just sort of the cowardly response to it. It’s like a cancellation tactic,” Sacks said. “And I think the reason why they’re doing that is because, quite frankly, there’s a lot of preference falsification going on in Silicon Valley.”

Cian O’Brien, an entrepreneur and former vice president for a Sunnyvale tech company, said he has become a pariah in Silicon Valley since pledging his allegiance to Trump. He said he had supported Democrats throughout his life, though he did not vote for President Obama. After donating to former Secretary of State Hillary Clinton’s campaign in 2016, O’Brien, 56, said he switched his support to Trump after he saw how “the apparatus” — media and other governmental institutions — went against him.

“They consider him a threat, because there he’s going to expose or crack down on … whatever their particular set of operations are,” O’Brien said. “And most of the operations are around people enriching themselves with power and money.”

Nibbling on sliders with American flag toothpicks, mini lobster rolls and a dessert buffet, attendees to the Sacks fundraiser included the Winklevoss twins, famed for their feud with Mark Zuckerberg about the creation of Facebook; Coinbase executives; and some AI leaders. Ohio Sen. J.D. Vance and North Dakota Gov. Doug Burgum, who are reportedly being vetted as Trump’s potential running mates, also attended.

Trump spoke for about an hour on a wide range of topics, including AI, cryptocurrency and being the victim of deepfakes, prompting a young AI executive to give a detailed explanation about using encrypted keys. He also argued that the world was safer under his administration, the border more secure, and he railed against transgender women being allowed to play in women’s sports.

The former president did not directly address the 34 felony counts he was convicted of last week, but he spoke broadly about the judicial system, Dhillon said.

“He was in great spirits. He said that there were some terrible judges out there. He didn’t get specific; he knows he’s under a gag order,” she said. “He said Republican judges go out of their way, bend over backward to look like they’re being fair, to be fair to the other side. And that Democrats are salivating, can’t wait to get their hands on the gavel and do what they want politically.”

Outside Sacks’ multimillion-dollar residence, police barricaded six city blocks surrounding the Pacific Heights residential enclave. Some attendees rolled up inside black Escalades, while others came on foot or motorcycle. Many arrived in pickup trucks waving large flags that read “Trump 2024.” One driver exchanged fist bumps with a bystander while at a stop sign. A group of middle school-aged girls stood nearby, donning Trump baseball caps.

“It’s a historical event,” said Jen Kelly, 60, of Sacramento, who called herself a lifelong Republican. “I know it’s a private fundraiser, but the fact that Trump is in California is very rare.”

After his swing through Silicon Valley, Trump traveled south, with fundraisers in Beverly Hills and Newport Beach planned for the weekend.

Sosa reported from San Francisco. Ahn, Mehta and Pinho reported from Los Angeles.