Tech entrepreneur Andrew Yang will talk a lot about giving every U.S. citizen $1,000 a month for life in the first Democratic presidential debate next week. It’s called universal basic income, and it’s Yang’s big issue. But it’s theoretical to him — he’s never held elective office.

Stockton Mayor Michael Tubbs has been running a pilot program on basic income in his city since February. And the whole world is watching to see how it works in a city that has no shortage of problems, starting with a 22% poverty rate, according to federal data.

“Give me something crazy because poverty is crazy,” Tubbs told his staff shortly after he was elected mayor in 2016. “Give me something crazy to fix it.”

They suggested giving residents a basic income. Tubbs balked at first.

“No way. It’s my first year as mayor. I don’t think I could do this,” Tubbs, on a recent episode of The Chronicle’s “It’s All Political” podcast, recalled telling his staff. Stockton had exited bankruptcy protection just a few years before, and Tubbs was wondering, “Where’s the money going to come from?”

The idea of giving people a basic income floor has been around for centuries — American revolutionary Thomas Paine mused about it — but it has rarely been implemented. Test programs have been conducted in Finland and Canada. But Stockton (population 310,476), where 130 families have been receiving $500 a month since February, is the first U.S. city to conduct a pilot program. The Stockton Economic Empowerment Demonstration is being funded by private donations, including one by an organization led by Facebook co-founder Chris Hughes.

Tubbs first heard about the concept as a student at Stanford when he read the Rev. Martin Luther King Jr.’s final book, “Where Do We Go From Here: Chaos or Community?” King argued that a universal basic income would be “the most effective” way to combat poverty.

“I was like, wow, I wonder what happened to this idea,” Tubbs said. “It would be interesting to have a conversation about the merits of this idea ... to see, would this work or not?”

Tubbs, 28, has a personal reason for being drawn to the concept. He was born to a single, teenage mom and grew up poor in Stockton. His father is serving a life sentence for robbery and kidnapping.

Tubbs’ mother kept his focus on school, and it paid off with a full scholarship to Stanford, where he earned undergraduate and master’s degrees. He was an intern, first at Google and then in Barack Obama’s White House, but decided to return home to Stockton after receiving a call from his mother on Nov. 1, 2010. A cousin, Donnell James, had been murdered at a Halloween party the night before.

It’s not unusual for young black men in Stockton to be killed, Tubbs noted.

“But this was a family member. It was someone I had birthday parties with, sleepovers with, church with, and just the expectation that, as family, we would go through life together.”

Tubbs’ first response was “a sense of nihilism.”

“Like nothing would change, so why should I care? Why should I try? Let me just make a bunch of money so myself and my family are comfortable,” Tubbs said. “But then it turned into, maybe there is something for me to do. Maybe there is a purpose to be found in this pain. Maybe there is a way for me to use this so that other people don’t have to experience it as well.”

That helped fuel his desire to see if a universal income can pull Stockton out of its long cycle of poverty and violence. Tubbs knew what his mom could have done with a steady check every month.

“Maybe she could have taken off work to go on some field trips” when he was in school, he said. Maybe she could have gotten a community college degree. At the least, Tubbs said, she wouldn’t have been forced to use “check-cashing places” to do the family’s banking.

Maybe “I would have (had) my own shirts rather than have my girl cousin’s shirts with all the ruffles,” Tubbs said. “It could have meant more agency, more opportunity and more dignity. Which is why I’m so passionate — not that we take care of everything for everyone, but the things necessary for people to live, particularly when we have the resources to do it.”

The 130 residents in Stockton’s pilot program live in neighborhoods where the median income is $46,033. Some recipients earn nearly twice that amount; some earn as little as $10,000. That diversity is intended to blunt criticism that “the money is only going to ‘those people,’” Tubbs said.

The researchers studying the pilot program are looking at a few key outcomes, including: How are recipients spending the $500 a month? Are there any effects on their health? Does having that extra cushion make their income more stable?

The early returns have been eye-opening for Tubbs. One man used the money to buy dentures. A woman used it for a car payment. Another woman told Tubbs that she finally feels “seen” by government leaders she long mistrusted.

Tubbs and other city leaders will study the results and decide on next steps. But he said that if the program were to continue — or scale up to include more people — the funding would have to come from the state or federal government. Stockton can’t fund a basic income on its own.

Tubbs doesn’t believe a basic income would “be a panacea for all of society’s ills.” But what happens with the Stockton experiment will affect the public’s reaction to similar programs that Yang and some of the other Democratic presidential candidates are pitching.

California Sen. Kamala Harris is proposing to give a $500 monthly tax credit to families earning less than $100,000. New Jersey Sen. Cory Booker wants to give every child $1,000 when they are born. Then, every year until the child turns 18, the federal government would give each child up to $2,000, depending on the family’s income.

Not everyone is a fan of what Stockton is trying. Former Alaska Gov. Sarah Palin tweeted in April, “You’ve got to be kidding,” along with a link that called the program “socialist.”

You've got to be kidding... https://t.co/UoJq0Mmwu1 — Sarah Palin (@SarahPalinUSA) April 2, 2018

Tubbs responded that the program was modeled in part on the Alaska Permanent Fund. The four-decade-old program — which Palin expanded as governor — gives state residents a stipend each year from a fund generated mostly by oil-drilling rights. Last year, every Alaskan received $1,100.

Actually modeled after the Alaska Permanent Fund. Are you familiar with it? https://t.co/RM33oa1w9S — Michael Tubbs (@MichaelDTubbs) April 2, 2018

Tubbs responded to Palin that the Stockton program was “actually modeled after the Alaska Permanent Fund. Are you familiar with it?”

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