Security was tight at Sen. Kamala Harris’ presidential campaign kickoff rally in Oakland: More than 200 city police officers worked overtime for the January event.

That doesn’t come cheap, it turns out. Paying police alone racked up a bill of more than $187,000, according to an invoice the city sent to the California Democrat’s campaign.

Some of the bills that the campaign has already repaid: $5,000 to the Oakland Fire Department and $8,000 to the Alameda County Sheriff’s Office, according to Federal Election Commission filings.

Harris’ campaign has so far paid $65,000 on the city police tab and has until next month to send the more than $122,000 remaining, according to the city.

Such bills are common — the city doesn’t help out candidates for free. “In terms of paying for events, for overtime for police or city services, I have to do that when I have my events,” said City Councilman Noel Gallo, chair of the Public Safety Committee.

The money it cost Oakland was only the start for the Harris campaign — it paid the Sacramento events production company Legion AVS received about $485,000 to put on the rally.

The Jan. 27 campaign kickoff was widely seen as a success. Organizers estimated a crowd of 20,000 turned out, making the event one of the largest campaign roll-outs among the Democratic primary field.

Harris also had one the biggest post-announcement polling bumps, according to the news site FiveThirtyEight.

The rally had a distinctly patriotic theme. Organizers were adamant about draping American flags from Oakland City Hall and got approval only hours before the event, thanks to help from Mayor Libby Schaaf.

Kimberly Veklerov and Sarah Ravani are San Francisco Chronicle staff writers. Email: kveklerov@sfchronicle.com sravani@sfchronicle.com Twitter: @kveklerov @sarravani