SACRAMENTO — The California Republican Party elected Jessica Millan Patterson as its chairwoman Sunday, making her the first woman and first Latina to lead the 140-year-old organization.

The 38-year-old Patterson, a longtime political operative who was raised in Hacienda Heights (Los Angeles County) and lives in Ventura County, promised to expand the beleaguered party into communities of color. Latinos and Asian Americans in particular have been fleeing the party for decades as the GOP adopted harsh rhetoric and restrictive policies on immigration.

“Let’s serve notice to the Democrats in California that we are back and we are ready to deliver on the Republican comeback,” Patterson said Sunday. “We’re going to take the fight to Democrats. We’re going to fight them in the press, at community gatherings ... and we’re going to beat them in elections.”

Patterson has long-standing ties with the party’s deep-pocketed donors as executive director of California Trailblazers, an organization that trains Republican candidates. She has extensive experience in the field, having worked on GOP campaigns for former Gov. Arnold Schwarzenegger, 2010 gubernatorial candidate Meg Whitman and 2008 presidential candidate Rudy Giuliani.

Patterson, whose paternal grandfather was born in Mexico, stressed that her top priority will be broadening the party’s appeal beyond its base of white voters. On Sunday, the 1,383 delegates meeting at the Sacramento Convention Center also elected Peter Kuo, who is Taiwanese American, as party vice chair and Greg Gandrud, who is openly gay, as treasurer.

“We need to get back into communities. We need to start engaging people. People are not going to reregister as Republican as long as they think that we are one thing,” Patterson said Saturday during a candidates debate. “We need to make them feel comfortable and welcomed into our party. It’s going to be the solution for a lot of our issues.”

Patterson won 54.6 percent of the vote in the chair’s race to defeat former Orange County Assemblyman and 2018 gubernatorial candidate Travis Allen, who got 30.7 percent, and longtime party activist Steve Frank, who won 14.7 percent.

On Sunday, Patterson invited Allen and Frank to lead a task force on improving the party’s voter registration efforts. Republicans now make up only 24 percent of California’s registered voters, trailing not only Democrats but people who decline to state a party preference.

Allen had criticized Patterson as a representative of the state party’s failed establishment. He noted that she was endorsed by nearly every Republican in the state Legislature, many of whom served with Allen in Sacramento, along with House Minority Leader Kevin McCarthy of Bakersfield. Allen said those endorsements and her leadership of California Trailblazers were an “example of the failing status quo.”

Other Republicans, however, hoped Patterson would help Californians take a second look at the party.

“She’s a woman, she’s a Millennial, she’s Latina — she’s looks like the future. She looks like California,” said Todd Cranney, a national political consultant who worked with Patterson on the Schwarzenegger and Whitman campaigns. “And she’s the best political operative I’ve ever worked with.”

Cranney, who now lives in Idaho, was one of several national political consultants who flew in for the weekend to support Patterson, “a sign that people are excited about the party again,” he said.

“To have a woman at the top, yes, it sends a different message,” said Assemblywoman Melissa Melendez, a Republican from Riverside who supported Patterson. “It widens the tent for the Republicans.”

Patterson is a strong social conservative, particularly on abortion. She is married and has two young daughters. She promised that, as chair, she would not be giving long speeches.

“My parents told me that talk is cheap,” Patterson said Sunday. “Your actions speak louder.”

Joe Garofoli is The San Francisco Chronicle’s senior political writer. Email: jgarofoli@sfchronicle.com Twitter: @joegarofoli