Jesse Arreguin, the ultraliberal Berkeley city councilman who in December will become Berkeley’s youngest and first Latino mayor, symbolizes the city’s new political order.

Arreguin beat eight candidates, including a more moderate Democratic city councilman, Laurie Capitelli, who was widely seen as the heir apparent to retiring Mayor Tom Bates. Some insiders saw Arreguin’s win as a changing of the guard in Berkeley: In addition to Arreguin, voters elected two new city council members, Sophie Hahn and Ben Bartlett. Another challenger, Cheryl Davila, is poised to unseat incumbent City Councilman Darryl Moore.

But others viewed the election results as a referendum on downtown development. During his eight-year tenure on the City Council, Arreguin, 32, has opposed Bates’ and Capitelli’s vision of tall, dense buildings near transit corridors. In 2014, he and Hahn, who was then a member of the city’s Zoning Adjustments Board, pushed an ill-fated ballot measure that would have imposed strict affordable housing, labor and environmental requirements on new real estate projects, making them prohibitively expensive to build.

Voters rejected the ballot measure by an overwhelming 74 percent. Two years later, they elected Hahn into city office and backed Arreguin for mayor.

“You have to ask if this is a reflection of people not wanting change,” said Arreguin’s opponent Capitelli, who holds the North Berkeley district seat that Hahn will take in December. He said two factions of voters found a “natural ally” in Arreguin: One faction wants to stop growth entirely. The other believes the city is not demanding enough from developers in return for their permits to build.

Arreguin, in contrast, saw the election as a race between a young progressive and an old-guard figure. Capitelli is a Realtor who amassed strong support from the industry. Arreguin had the backing of the Service Employees International Union and an endorsement from Sen. Bernie Sanders, which helped propel him to victory.

“It was a very clear choice between me and my opponent, who has literally rubber-stamped every (real estate) project that came before this council,” Arreguin said in an interview Friday.

Capitelli’s campaign manager, Jill Martinucci, recoiled at that depiction. “Laurie doesn’t support razing neighborhoods to build big buildings, but he got characterized that way,” she said. “I think this was a reactionary election.”

The fight over what Berkeley’s downtown should look like has created stark divisions in City Hall for years, with some officials crying out for more housing and commercial projects, while others fear the arrival of wealthy newcomers and tall buildings that will blot out the horizon.

“In talking to thousands of Berkeley voters, development and the housing crisis were their top concerns,” Arreguin said. “People of my generation — the Millennials — were concerned about their ability to afford to live here because of rising rents. Long-term residents were concerned about the changing face of Berkeley: they think these buildings are ugly, they worry about the scale, they think there is no real plan for bringing in thousands of new residents.”

Last year the battle largely hinged on a single project — an 18-story apartment complex at 2211 Harold Way, which drew opposition because of its height, its lack of affordable units, and fears that it would partly block a view of the Golden Gate Bridge from UC Berkeley’s Campanile tower. The City Council approved it in December and asked the developer, HSR Berkeley Investments, to contribute a huge community benefits package, which included union construction labor and $10.5 million for the city’s affordable housing fund. Arreguin abstained from the vote.

Two opponents sued to block 2211 Harold Way in January, but an Alameda County Superior Court judge dismissed their case in October. The project appears to be slowly moving forward.

While some residents in Berkeley despair over big high-rises, the city also faces scrutiny from the other side: A group of build-it city dwellers from the San Francisco Bay Area Renters’ Federation — which goes by the name SFBarf — sued the City Council on Oct. 7 for denying permits to a modest three-house development at 1310 Haskell St. According to the suit, the council violated the state’s Housing Accountability Act, which bars cities from rejecting development for arbitrary reasons — in this case, because neighbors complained. A Superior Court judge ruled in SFBarf’s favor on Oct. 21, ordering the council to schedule a new permit hearing for the project.

Representatives of SFBarf and of another pro-development group called East Bay Forward say they are watching Berkeley closely and will try to influence a special election to fill Arreguin’s council seat early next year.

“I’m extremely disappointed about the local election results,” said Garret Christensen, an economics researcher at UC Berkeley and member of East Bay Forward.

Hahn and Arreguin say they speak for a large and diverse group of Berkeley residents who want new leadership, but don’t want fundamental changes to the city’s skyline.

“People are afraid of losing things that make Berkeley worthwhile — authors, artists, activists, teachers, working families — and they bristle at the thought of a luxury high-rise with not one unit of affordable housing,” Hahn said.

She sees Berkeley’s newly elected leaders as a response to the political dynasty embodied by Bates and his wife, retiring state Sen. Loni Hancock.

“I think politics in Berkeley and in the East Bay have been very dominated by a small group of people for a long time,” Hahn said. “They’re people who have given a lot of good service to the community but who have had power over who gets elected and whose agendas move forward.”

To Bates, the election was mostly about personalities: Arreguin was seen as the new young mayor, while Capitelli was bedeviled by his real estate industry connections.

“In Berkeley, you have ‘left,’ and ‘more left,’” Bates said. “And now the ‘more left’ has taken control, but they’re NIMBYs. So we’ll have to see how that plays out.”