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LAREDO, Texas — They're both children of Texas who share similar backgrounds.

But they also epitomize the generational divide that is showing up in politics as more young Latinos come of voting age and become part of the political class.

Jessica Cisneros, 26, an immigration and human rights lawyer, is challenging Rep. Henry Cuellar, 64, in Tuesday's Democratic primary for the U.S. House seat Cuellar has held for 15 years.

Once seen as a long shot, Cisneros has pushed Cuellar to take her challenge seriously.

The charged race in the 28th Congressional District has become as important to some voters in South Texas as the Democratic presidential nomination contest on Super Tuesday — and it has been drawing national attention.

"This is going to be generational change" if Cisneros wins, said Denisce Palacios, 22, a volunteer for her campaign and campus organizer for Texas Rising, a young Latino activist group that endorsed Cisneros.

Cisneros is the child of Mexican immigrants who gained citizenship through the 1986 immigration law signed by President Ronald Reagan. Cuellar is the son of migrant workers, both born in the U.S., and one of eight children.

Facing his first major challenge in years, Cuellar brought in powerful allies, such as House Speaker Nancy Pelosi, D-Calif., to shore up his standing with district voters. Political money from organized groups is coming in for both campaigns. Cisneros has the support of several high-profile progressive leaders, including Rep. Alexandria Ocasio-Cortez, D-N.Y.

Working hard "just isn't enough"

Cisneros is adamant that she isn't waging a youth or progressive rebellion. To her, the campaign is about economic struggle and a belief that Cuellar's Blue Dog Democrat platform is out of step with those who need his help most.

"It's not so much a generational divide, at least for us, because we have had a very high poverty rate for a long time here in Laredo," she said in an interview between knocking on doors to ask for votes Saturday afternoon.

In a kickoff of a four-day canvassing marathon, Cisneros said she lost family members who couldn't get health care and that is her "why" for seeking election.

Her aunt was diagnosed with stomach cancer, she said, and fell into a coverage gap of being too well off to afford government assistance but too poor to pay for it, "so she passed away."

"Here, inability to access medical care means you have to go to Mexico to go get treatment, means you have to go sell plates of food on the side of the highway, you have raffle tickets — to be able to pay medical costs," she said. "We did all that."

Jessica Cisneros, running for Congress in the Texas Democratic primary against Rep. Henry Cuellar, at her campaign headquarters in Laredo. Suzanne Gamboa / NBC News

Texas' 28th Congressional District stretches from the U.S.-Mexico border to northeast San Antonio, combining urban and rural communities. It is 78 percent Hispanic — a term used as much or more than "Latino" here.

Almost a quarter of the district's population lives below the poverty line, which is about 1½ times the poverty rate of the rest of the state and nearly double the U.S. rate, according to the Census Bureau.

"There's a lot of folks who work two and three jobs just to make ends meet, across the age range, where working so hard just isn't enough," Cisneros said.

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High schooler Angel Olmos, 19, is earning $15 an hour working for Cisneros' campaign. He lives with his mother and two brothers in a $750-a-month apartment where they moved after being late with rent a couple of times when they were living in a house.

His mother works from 9 a.m. to 9 p.m., while he and his brother care for their younger brother. She is adamant that he focus on his education, he said.

A grandmother and a great grandmother worked all their lives yet have always struggled for basics. The family crosses the border into Mexico when possible to get more affordable treatment and medicine for the elder women's arthritis.

"We are told if you work hard enough, you'll make it," Olmos said. "This is three generations of working hard and not making it."

"Worked his way up"

To start his last weekend before Super Tuesday, Cuellar traveled up to Atascosa County in the northwestern part of the district, to announce plans by the Air Force to use an air strip in the rural area.

Cuellar, the only Texas Democrat on the House Appropriations Committee, says this is the sort of thing he's done for the district — brought attention and projects and federal funding and jobs.

Cuellar was once in Cisneros' shoes; in 2004, he challenged and defeated Rep. Ciro Rodriguez for the seat in the primary. Rodriguez was based in San Antonio then.

"I always felt the border area did not have representation, so we brought a congressional seat to the border area," Cuellar said.

But Cuellar got a cold reception in Washington, not only for challenging an incumbent, but also because of his closeness with Republicans.

He had endorsed Gov. George W. Bush for president over Democrat Al Gore and served as Texas secretary of state under former Republican Gov. Rick Perry. A photo of Bush cupping the cheeks of a smiling Cuellar at the 2006 State of the Union address further angered Democrats.

But Cuellar has been re-elected several times since then, even while voting at times against his party on such issues as guns and border security. He has risen in the ranks of party leadership and has amassed an endorsement list of some 250 local officials. His brother, who is the sheriff of Webb County, and his sister, the county tax assessor-collector, are running for re-election.

"I've lived here all my life, and I don't go and call it a liberal seat," he said. "I vote the way it is, and you know, if I was so out of sync. I think the voters would have said goodbye to me a long time ago."

Phonebanking again tonight before heading back to the Capitol for votes. I am humbled by the great responses we are getting. Thank you to our supporters and volunteers! pic.twitter.com/EPzWKygYKs — Henry Cuellar 2020 (@CuellarCampaign) February 4, 2020

Cuellar sees the challenge from Cisneros as being driven by out-of-town groups, such as Justice Democrats, a progressive political action committee that seeks to replace "corporate-backed" members of Congress, which backed Ocasio-Cortez. Cuellar calls the PAC "Justice Socialists."

"They think that if you are Hispanic you have to be far left, and that's wrong," he said.

Cuellar points out as an example that 108,000 people have jobs in the district because of oil and gas. "I don't see my district saying get rid of the oil and gas," he said.

On his canvassing jaunt Saturday, Cuellar walked through a neighborhood where many of the elder residents have known him for years.

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Pablo Lemos Jr., 72, spotted Cuellar while driving through the neighborhood and pulled his red pickup over to assure him of his support.

"He's doing a great job, even if we don't see him that much," he said. He mentions that Cuellar speaks English and Spanish well and recalls his speaking at an event and telling the audience not to be afraid to use both languages.

Of Cisneros, he says she's a good candidate but "real young."

Later, Socorro Garza, 78, steps onto her porch to greet Cuellar and reminisce. She had been his boss when he worked as a lawyer to help the Laredo Morning Times collect unpaid bills.

She said she is happy to see younger Latinos engaged in politics and believes "the old have to go and the young have to go in," but she wants to see Cuellar re-elected.

"Where is her experience?" she asked of Cisneros. "He started as an attorney, and he went on to state [government]. He worked his way up, and that's the only way you can know what is going on. You have to start from the bottom up."

Older voters are more reliable voters, but Latinos skew younger, and their turnout has improved in recent elections.

Democratic primary congressional candidate Jessica Cisneros signs her campaign material before hanging it on a doorknob in Laredo, Texas. Suzanne Gamboa / NBC News

In Texas, about 15 percent of all Latinos who voted early in the Democratic primary were under 30, according to an analysis of state data by the Texas Organizing Project. In comparison, 12 percent of all early voters in the state were under 30.

Palacios of Texas Rising said that complacency is not part of the Latino culture and that "we are taught to work hard for everything we have." But, she said, the humility in the culture can be Latinos' downfall.

"What we are taught is to be just grateful — our parents taught us to be grateful when you have the bare minimum," Palacios said. "In this new generation, we are realizing we can wake up and build our power and create the change we want to see."

For her, it starts with a victory for Cisneros on Tuesday.

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