Bernie Sanders makes surprise visit to Oakland campaign office

OAKLAND, Calif. (KGO) -- Democratic presidential hopeful Bernie Sanders is confident he'll win tonight's West Virginia primary.

Sanders was in Stockton and the Bay Area Monday, where he said he's the only one who could beat republican Donald Trump.

On Monday, Sanders made a surprise visit to his campaign office in Oakland.

RELATED: California primary: Early voting begins across the Bay Area

Sanders made it very clear that he not only needs to win all future primaries, but that he needs to win big.

He showed his easy going personality off walking down College Avenue as he greeted supporters and it was a visit few expected, but that many had hoped for.

Sanders said he expects to win the West Virginia primary and hopes to do the same in California, even if Hillary Clinton is dominating the delegates count, Sanders told reporters that he's the only one that can beat Republican contender Trump. "First day we were in this campaign, nobody thought that we would be fighting here, and stand a good chance to win in California on June 7, so an uphill fight is not something that gets me nervous, that's what I've been doing from day one.

RELATED: Estimated 15,000 attend Bernie Sanders rally in Sacramento

Word about Sanders arriving at the Oakland office started out as a possibility and quickly spread on social media.

On Sunday night, Sanders was in Sacramento addressing about 16,000 people and Monday morning he attended a rally in Stockton.

On Monday afternoon, Sanders stopped at a San Francisco coffee shop for sitting down with the editorial board of the San Francisco Chronicle.

Officials said he will be in Oregon Monday night.

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