New polling shows Mahan in sixth place, but the two-term mayor said voters are only beginning to engage as ballots arrive.
"I'm very motivated because there's so much at stake for Californians. We deserve better than the outcomes we've been getting," Mahan said in a one-on-one interview.
Campaign activity has intensified in recent weeks, with candidates launching new ads, events and outreach efforts in a final push before Election Day.
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Asked whether it is too late to make up ground, Mahan rejected the idea.
"Not at all, people just got their ballots," he said. "We've grown faster in the polls in the last couple of weeks than anybody else; we've doubled. And when voters get to know who I am, what I've done in San Jose and my vision for the state, we go up."
Mahan pointed to his record in San Jose as evidence that his approach could resonate statewide, particularly on issues such as housing and homelessness.
When pressed on criticism that, despite progress, San Jose continues to face visible challenges, Mahan argued that results are key to restoring trust in government.
"Look, Donald Trump thrives when Democrats fail to solve problems," he said. "The best antidote to authoritarianism is delivering results. It's making government work and actually make people's lives better. I'm proud of the progress we've made in San Jose."
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Among his proposals, Mahan highlighted interim housing as a scalable solution.
"Interim housing. We've built 2,000 spaces, mostly individual rooms with doors that lock where people can come immediately off our streets and find safety, stability and get connected with services that help them turn their lives around," he said.
The issue remains politically sensitive in San Jose. On Tuesday, the city moved to close its only sanctioned tent encampment due to budget cuts, but Mahan defended the move.
"Well, it shows that we're willing to try things, we have to prioritize," he said. "And that's not a reflection on anything other than the fact that we've got to choose the solutions that have the highest impact."
Mahan said housing affordability remains at the center of his campaign message.
"It would be building a lot more housing so that young people, working people, could afford their housing and afford to become homeowners and have the stability and the peace of mind that comes with owning a home," he said.
With less than three weeks until the June primary, Mahan's campaign faces a narrowing window to convert increased visibility into votes as Californians continue casting ballots ahead of Election Day.