Sanders compares his campaign to Warriors comeback

OAKLAND, Calif. (KGO) -- Senator Bernie Sanders is spending the night in the Bay Area after a full day rallying supporters - even attending the Warriors game.

A cheering crowd greeted presidential candidate Sanders outside Oakland City Hall, where he compared himself to the Golden State Warriors.

"They were down three games to one right? They came back, yes? Well, we started pretty far behind, I think we're going to come back as well," said Sanders.

At least 20,000 Bernie Sanders supporters gathered at Oakland's Frank Ogawa Plaza to hear the presidential candidate speak.

WATCH: Estimated 20,000 people attend Bernie Sanders rally in Oakland

This was the second of two Bernie Sanders events in Oakland on Monday, and this one was moved up to avoid being at the same time as the Warriors game.

During the rally, Sanders touched on his familiar themes - getting big money out of politics, his plan to make public college tuition-free, climate change and universal healthcare.

Ahead of next week's primary election, both democratic candidates have their eyes on California. Hillary Clinton is changing her campaign plans and returning to California for 5 days.

"I think maybe we are making her a little bit nervous," said Sanders.

Sanders supporters say Clinton is feeling the 'Bern.'

"It sounds like she's scared because she refuses to debate with him and she's adding on days here," said Laura Diesman, a Sanders supporter.

RELATED: Bernie Sanders attends Memorial Day event in Presidio

Earlier in the day, he made an unannounced stop at a Memorial Day ceremony in San Francisco and spoke at Allen Temple Baptist Church in Oakland.

Approximately 10 minutes into his rally outside Oakland City Hall, animal rights activists rushed the stage. Secret Service agents cuffed and removed them.

Sanders supporters started lining up here much earlier in the morning, before the gates opened. The line extended all the way around the downtown area. Oakland police estimate the crowd topped 20,000.

Sanders plans to spend even more time in the Bay Area, his campaign announced, adding to the California swing.

On Tuesday, a press conference on health care is planned for the morning in Emeryville, followed by rallies in Santa Cruz and Monterey.

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