Updated 7:15 p.m.: Revised to include additional information.

GRAPEVINE — Texas leaders like to poach companies from California; now presidential contender Kamala Harris is looking to pluck delegates — and money — from the Lone Star State, where Beto O'Rourke and Julián Castro are the favorite sons.

Friday night the Democratic senator from California was in Grapevine for a "conversation" with Tarrant County Democrats led by the group's chairwoman, Deborah Peoples.

"I know and do know and will know how to prosecute the case against Donald Trump," Harris, a former prosecutor and California attorney general, said as the Grapevine crowd gave her a standing ovation.

Harris also had a message for the younger voters and students in the room.

"Always know that something worth fighting for is a fight worth having," she said. "If you approach issues in a way that you try to find common ground but hold firm to principles that you know that are right, it will be worth it.

"The reason we're all here today is that we love our country, and we know our country is worth fighting for," Harris added.

The event is part of her two-day swing through Texas. On Saturday she's holding a rally at Texas Southern University, a historically black college in Houston.

Most Texas visits from out-of-town candidates come with a pitch for money, so Harris headlined a fundraising reception in North Dallas. The event attracted several North Texas leaders, including Ron Kirk, former U.S. trade representative and Dallas mayor; state Sen. Royce West; and Plano Mayor Harry LaRosiliere.

Harris' raid on her rivals' territory is indicative of the close, complex Democratic race for president, where the formula for delegate selection encourages competitive races across the country, even on the home turf of fellow Democrats. O'Rourke and Castro will get plenty of opportunities to retaliate, given that California, like Texas, holds its presidential primary next March 3.

Texas is the second-biggest prize in that Super Tuesday presidential primary, when more than half the delegates for the nomination will be at stake. Though O'Rourke, the state's most popular Democrat, is expected to roll up big numbers in his home state, the proportional system of how Texas' 149 "district delegates" are awarded allows opportunities for Harris and other Democrats to come away with support. Texas has 262 total delegates at stake, according to a draft delegate-selection plan that will be delivered to the Democratic National Committee.

"It's all going to be split up," said Texas Appeals Court Judge Ken Molberg, a veteran of many presidential campaigns and a former member of the Texas Democratic Party's executive committee. "Numerous candidates can compete for Texas delegates."

A case in California when Sen. Kamala Harris, pictured above during the confirmation hearings for Brett Kavanaugh, was the district attorney in San Francisco has taken on new relevance as she seeks the Demoratic nomination for the presidency. (Washington Post photo by Melina Mara) (Melina Mara / The Washington Post)

How Harris could get delegates

Harris, in particular, is expected to perform well with black voters and women, the most reliable base of the Democratic Party. Black women voters are influential in Tarrant County and Houston, the places Harris is visiting. But they are also influential in areas like Dallas, East Texas and even enclaves in Central Texas.

If Harris wins the black vote, she could perform well in Texas.

"It's incredibly smart for Sen. Harris to reach out to Tarrant County's diverse community of voters," said Royce Brooks, the executive director of Annie's List, a group committed to electing progressive women who support abortion rights to the state Legislature.

Brooks, a Fort Worth native, said Democratic women were able to win critical elections in Tarrant County last year.

"Tarrant voters really demonstrated an appetite for progressive change and a willingness to support strong women leaders in 2018 by electing two new Democratic women — Sen. Beverly Powell and [Tarrant County] Commissioner Devan Allen," Brooks said. "Kamala Harris may be the first female presidential candidate to come to Tarrant this cycle, but I'm certain she won't be the last."

Harris is the latest of several presidential hopefuls to have recently campaigned or made appearances in North Texas.

On Monday former Housing Secretary Julián Castro campaigned at St. Pete's Dancing Marlin in Deep Ellum. Earlier this year the former San Antonio mayor had a fundraiser and mixer at Mercado in North Oak Cliff.

For the Texas primary, Castro is expected to garner support from Hispanic voters across the state and roll up delegates in South Texas and the Rio Grande Valley.

Presidential candidate Julian Castro speaks during a campaign event at St. Pete's Dancing Marlin in Deep Ellum on Tuesday, March 19, 2019, in Dallas. The former San Antonio Mayor met with Democrats in Dallas on Tuesday after campaigning for the Democratic Party nomination in New Hampshire on Monday. (Smiley N. Pool/The Dallas Morning News) (Smiley N. Pool / Staff Photographer)

Contenders from outside of Texas also have visited the Dallas area.

In February, Sen. Kirsten Gillibrand of New York held a town hall for students at Paul Quinn College in southern Dallas before attending a fundraiser on her behalf hosted by prominent Texas political donors Naomi Aberly and Aimee Boone Cunningham.

And in January former Vice President Joe Biden discussed his latest memoir in Grand Prairie. Biden is popular with Texas Democrats and a threat to the home state rivals.

Then there's O'Rourke.

Though the El Paso Democrat hasn't been to North Texas since November, when he lost a close Senate race against Republican incumbent Ted Cruz, the memory of his dramatic campaign still resonates.

O'Rourke won Tarrant County, which had been dominated by Republican voters for decades.

"We generated 313,000 votes for Beto O'Rourke," Peoples said.

Tarrant opportunity

But Tarrant County's diversity creates opportunities for others, particularly in its high-voting black neighborhoods.

There are 149 delegates up for grabs in the state's 31 Senate districts. The delegate-allocation formula will be based on results from the 2016 and 2018 elections. The places with the most Democratic votes will have the most delegates.

Urban areas concentrated with black and Hispanic voters could help Harris reach the threshold needed to get a share of delegates.

"We know that Tarrant County is a vote-rich area for Democrats," said Peoples. "It's a great place for all the presidential candidates to campaign for the presidential primary."

Peoples says she's invited every Democratic presidential candidate to mingle with Democrats in her county.

"Everything you're doing matters," Harris told Tarrant County Democrats, praising them for making the county more competitive.