GRAPEVINE, Texas — Texas Democrats are hoping a blue tide won't ebb in a county once considered to be among the country's most conservative large urban centers.

Tarrant County, which covers Fort Worth, Texas, had long been a Republican stronghold, supporting the GOP nominee in the 2008, 2012, and 2016 races for the White House. But last year, now-2020 Democratic presidential candidate Beto O'Rourke clinched it during his failed bid to oust Republican Sen. Ted Cruz from office. The area previously voted for Cruz in 2012.

After Friday night's visit from fellow 2020 presidential contender Sen. Kamala Harris of California, local officials told the Washington Examiner the Democratic National Committee, the state party, and other presidential hopefuls must invest resources in the county rather than spending easy time and money in its more liberal neighbor, Dallas County.

Marco Rosas Jr., who has been the Tarrant County Democratic Party's executive director since 2016, said the ground shifted for Democrats during the 2016 election cycle courtesy of a grassroots strategy implemented by the county party's chairwoman, Deborah Peoples, which focused on left-leaning voters who in the past had not been prioritized.

"2016 is what started it. Historically, we lose by 100,000 votes. We picked up 60,000 in 2016. And then what happens with Beto in 2018? We win," Rosas said after the Harris event. "Think about it this way. It's usually the same people going to vote, and it's the same people being talked to, and it's the same group, right? So it's the same people that we kept losing with year after year. We start expanding that. We find more people that are pissed off, because there's a million people getting pissed off, right? But them actually coming out and doing something, that's where the county party has to come in. We have to give them an outlet for all that anger."

While Sens. Kirsten Gillibrand of New York and Elizabeth Warren of Massachusetts, themselves White House prospects, have traveled to Texas over the course of their respective campaigns, Harris is the first to stop in Tarrant County. Rosas said Friday they were expecting another three by the end of the summer and hinted that there would be a special guest at their Blue Wave Ball on May 18.

"People know we're like a player now," he said. "Here's the thing. The sky's the limit. We still have so many votes left in Tarrant County."

Peoples, who has been chairwoman since 2013, on Friday acknowledged the role O'Rourke played in 2018 when he defeated Cruz by more than 4,000 votes in a county that is less racially diverse and affluent than Dallas County.

"Absolutely, Beto was a fantastic candidate. He was just a dream candidate, but I tell everybody it was like the perfect storm," she said. "We had this layer of 'Never Trumpers,' and a layer of 'Forever Beto,' but then we went in there and did that hard work that said, 'This is why you need to come out and vote.'"

Peoples, herself a mayoral contender for Fort Worth's local May 4 election, said Harris' visit was "amazing" because instead of raising money for herself, the former California attorney general brought in contributions that will help bolster the county's party-building efforts.

Though Peoples will not endorse ahead of the 2020 Democratic primaries, she encouraged other candidates to make stops in her district as well, adding that she had contacted Warren and Sen. Bernie Sanders of Vermont.

"We want them to come to Tarrant County. This is not Dallas. We're different and while we love Dallas, we are not Dallas and we face unique problems," she said, referring to the Democratic field. "I want people to come, listen to them, make up their own minds, but I want more than anything for them to be energized. I want them calling me tomorrow saying, Who's coming next?'"