SAN JOSE (KPIX) – Billionaire presidential candidate Mike Bloomberg will join former California governor Jerry Brown on stage for a conversation on climate change at San Francisco’s Moscone Center on Wednesday.

Meanwhile, San Jose Mayor Sam Liccardo is defending his endorsement of the former New York City Mayor after his surprise announcement on Monday.

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“We’ve got the biggest bully in the history of the planet occupying the White House, and I want to support those who can take down bullies,” Liccardo said.

Liccardo was an early backer of Senator Kamala Harris, who recently dropped out of the race and said she could not compete for the presidency against billionaires like Bloomberg.

Liccardo said Bloomberg is the only candidate left who can compete with President Trump.

“Mike Bloomberg has shown time and time again, that he’s willing to take on big oil, he’s willing to take on the gun industry, he’s willing to take on big soda, Coke and Pepsi.”

Liccardo is not just backing Bloomberg, he’s chairing Bloomberg’s California campaign.

“Michael Bloomberg isn’t well known in California, so, for Sam Liccardo to get out front with a candidate who’s polling really low but has lots of money is a surprise,” said San Jose State Political Science Professor Larry Sokoloff.

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Sokoloff said California has a history of voting down very wealthy candidates such as former tech executive Meg Whitman for governor in 2010.

Bloomberg is betting big on California, skipping early primaries to focus on Super Tuesday in March by blanketing the state with $14 million in TV ads.

But one San Jose activist and frequent critic of Liccardo says the mayor is making the wrong choice.

“There’s a lot of other candidates who are actually fighting for the middle class,” said housing advocate Shaunn Cartwright. “He chose the guy who supports stop and frisk, the guy who has a whole history of racial insensitivity.”

Liccardo had an answer for Bloomberg’s controversial New York policy that disproportionately targeted Black and Latino men.

“The truth is, he did reduce gun violence substantially in New York and all crime, nonetheless, as he recognizes today and I also believe that stop and frisk was the wrong policy,” Liccardo said.

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At Wednesday’s event, Bloomberg and Gov. Brown will be discussing, ‘America’s Pledge,’ the pair’s co-project launched in 2017, to ensure the United States remains a global leader in enforcing the climate goals of the Paris Agreement.