Speaking Monday, just days before the election, Mahan reflected on his motivations for running while honoring those who died in military service.
"Today has been an inspiring day. And as we head into the homestretch of this election, I'm just going to stay focused on solutions. That's why I'm in this race," Mahan said.
Recent polls show Mahan losing ground, and his campaign has faced scrutiny following developments involving campaign funding.
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A pro-Mahan political committee refunded $1 million to Netflix Chairman Reed Hastings, a major backer.
Additionally, Mahan faced a corruption complaint related to alleged coordination with a billionaire-funded political action committee.
Mahan said Hastings did not request the refund and continues to support his campaign. He also noted that the complaint was rejected.
"I would ask the media, though, to hold itself to a higher standard and really take the time to get the story right, rather than rush to have a very clickable headline that turns out a day later to be totally false," he said.
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Political observers say the financial developments and campaign activity may signal trouble.
Melissa Michelson, a Menlo College political scientist, said actions involving independent expenditure committees could reflect weakening support.
"Regardless, that independent expenditure committees are shutting down and are deciding to refund money. That's not good news for the Mahan campaign," Michelson said.
She added that the timing of these moves is notable.
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"To pull back before that last day of voting is really unusual for a campaign. And it's a sign that folks really just don't think this is going to happen for Matt Mahan," Michelson said.
If Mahan does not succeed in the primary, Michelson said he is expected to return full-time to his role as mayor after months on the campaign trail.
Despite spending significant time campaigning, Mahan said he has continued to fulfill his duties in San Jose, including issuing a budget message and proposing policy solutions.
"No matter how this plays out, at a minimum through the end of this year, I'm going to fully execute the job of mayor because the issues we have here are too important to slow down on," he said.
The election is approaching as Mahan and his campaign navigate the final stretch under increased scrutiny.