Kate Gallego knew she wanted to run for mayor of Phoenix, but the timing couldn't have been worse.

In 2017, she was serving on the Phoenix City Council when the outgoing mayor announced he was leaving to run for Congress, leaving the seat open.

"I had long been interested in running, but it was a rough time in my personal life: My mom had just been diagnosed with stage four cancer, and I was pregnant, and my marriage fell apart, so I was newly divorced with an infant," Gallego, now 43, told CNBC's Morgan Brennan at the recent 2025 Changemakers Summit in Los Angeles.

Gallego initially decided she couldn't pursue the mayoral seat: "It was too much. I felt like everyone was asking questions about my divorce and my personal life, and I didn't want to put myself in too much scrutiny over that."

But months after becoming a mother, she began to think otherwise. She was getting more sleep, for one, and also recognized that all around her were "wonderful people who wanted to support me and help me be successful in public service and be a successful mother," she told CNBC.

"I realized there wasn't a need to be a perfect mayor with your entire life in order," Gallego said. "In fact, it maybe makes you a better mayor if you're juggling the same challenges everyone else is and have the same pressures."

Gallego, a Democrat, ran for mayor and in 2019 became the second woman elected mayor in Phoenix history and one of the youngest big-city mayors in the nation.

Gallego said she was glad she took the leap and urges others to not wait for the "right" time to pursue their ambitions.

"If there's anyone out there and you're making a big life decision and you want to wait till your life is perfect, I would say, don't [wait]," she said. "At least, my life has never been perfect. But I think if you share what your goal is and what the vision is, what you hope to achieve, a lot of people are willing to help you along the way."

Gallego said sharing her experience connected her with the many others who had similar life moments, and "hopefully I will make it easier for the next mom who wants to do a career change or promotion."

"Just knowing that the people of Phoenix were very, very supportive, it did not end up being the huge issue that I thought," she said. "It worked out for me, but it was a lot of doubt along the way."

Leading Phoenix to be 'future-ready'

Gallego will be sworn into her final four-year term as Phoenix mayor on Monday and is ready to "make Phoenix as future ready as possible," she told CNBC.

Already, she has helped shape Phoenix as a hub of innovation, including by working with companies ranging from Amazon to Taiwan Semiconductor Manufacturing Company and Alphabet's Waymo on projects that are delivering packages and passengers to airports, and bringing new jobs and an influx of investments.

For example, TSMC's plans to invest more than $165 billion to build advanced chips in the U.S. have brought in new workers to Phoenix, and the city is one of three in the U.S. where Waymo robotaxis transport passengers in driverless vehicles.

A personal loss — one of Gallego's former bosses was killed in a traffic accident — has motivated her to invest in AI-powered traffic signals to improve pedestrian safety.

Meanwhile, Gallego said she's invested in initiatives that bring new high-paying jobs to underserved communities, like Navajo women who previously worked in the coal industry who now do iron work at the semiconductor plant in $100,000-plus roles.

"It's exciting to have four more years in the city of Phoenix," Gallego said. "We're in a really good place. We feel like we're the 'good news' branch of government, and so we're hoping to continue delivering results."

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