SF Mayor Breed will win election as mayor, but what about...

San Francisco Mayor London Breed is virtually assured of being elected Tuesday. It’s the other races on the ballot, however, that will determine whether it’s a real win for her or a hollow victory that could spell trouble for years to come.

“She’s playing a high-risk, high-reward game,” said political strategist Jon Golinger, who managed Jane Kim’s unsuccessful campaign in last year’s mayoral election.

There are two key races on the ballot: district attorney and District Five supervisor, the seat Breed used to hold in the left-leaning Haight and Western Addition. Her hand-picked successor, Vallie Brown, is in a tough race against tenants rights activist Dean Preston.

“If she wins both, she wins big. If she wins one and loses one, it’s a mixed bag. If she loses both, she’ll have to do a political reset,” Golinger said.

And in this political card game, Breed comes to the table with a mixed hand.

Recent polls show that while 56% of voters like Breed, only about 33% are happy with her performance as mayor. Polls also show that more than half of voters — 57% — feel the city is on the wrong track.

So Breed needs to show results in the coming year.

But for her to advance her carrot-and-stick approach to getting the homeless and the mentally ill off the streets, or pursue a crackdown on public drunkenness and open drug use, or step up the prosecution of petty crimes like auto break-ins, she needs an ally in the district attorney’s office.

And the outcome of the D.A.’s race is far from certain.

Going into the election, the four-way race appears to be wide open, with Nancy Tung, a deputy district attorney in Alameda County, staking out a law-and-order position on prosecutions; judicial reform candidate and Deputy Public Defender Chesa Boudin running on a “reform” platform that calls for fewer incarcerations; and Deputy Attorney General Leif Dautch and former Police Commission President Suzy Loftus, who come down in the middle.

The mayor’s public safety agenda would mesh well enough with Loftus, Tung or Dautch — not so with Boudin, who has made it clear that he will not criminalize the homeless by prosecuting quality-of-life crimes like public camping, prostitution and public urination.

Breed supports Loftus and appointed her interim district attorney when George Gascón resigned to run for the same job in Los Angeles. The appointment was widely seen as an attempt to boost Loftus in the public eye, and it was met with significant blowback by critics who saw the appointment as machine politics.

Breed faces another test in her former supervisorial district, where Brown is in a close race with Democratic Socialist Preston.

A Preston win would erode what little support Breed has in the progressive-dominated Board of Supervisors. Plus, it’s personal. Preston ran against Breed when she was a supervisor, and he probably will be a vocal opponent of Breed at City Hall if he wins.

Another must win for Breed is Measure A, the $650 million affordable housing bond she’s backing in a big way.

The Yes on A campaign’s polling shows the bond with about 70% support among voters, just above the two-thirds majority needed to pass. Most people familiar with San Francisco voting patterns are predicting victory.

Breed herself is a sure winner in her race, but given the recent polling numbers, insiders will be watching the vote count closely.

Here’s why:

She narrowly squeaked out a 50.5 % win in the final-round showdown with progressive former state Sen. Mark Leno in last year’s special election following the death of Mayor Ed Lee. This time out she’s facing only token opposition from five little-known candidates, but she needs to put big points up on the board.

A 65% to 70% showing would be a solid affirmation of Breed’s agenda.

However, a 55% vote — like Mayor Lee won when he ran largely unopposed in 2015 — could spell trouble, just as it did for Lee. He saw his approval ratings plummet following the election as the city continued to grapple with homelessness, jammed traffic and the affordable housing crisis.

And shock waves would follow.

“Being mayor of San Francisco is hard in the best of circumstances,” state Sen. Scott Wiener said. “People expect immediate results on intractable issues, and we are going through tough times.”

Wiener, who has worked with the mayor on a number of issues, said Breed’s poll numbers are more about frustration with challenges facing the city and less about Breed’s performance, which he characterizes as “very strong.”

Whatever the case, Breed is betting big this time out.

“She could have stayed out of the races, but she chose to put herself on the line,” Golinger said. “A lot of politicians do everything possible to avoid that kind of risk.”

Big spenders: More than $2 million has been spent on the race for San Francisco district attorney, with the biggest chunk coming from independent expenditure committees financed by law enforcement.

The biggest player is the San Francisco Police Officers Association, which has launched an 11th-hour, $669,867 media blitz against progressive, judicial reform candidate and public defender Chesa Boudin.

On the other side, a committee with the “when can I take a breath?” title of Youth and Families Taking Power Supporting Chesa Boudin for SF District Attorney 2019 has spent $188,767 to support him.

And it goes on. The San Francisco Deputy Sheriffs’ Association has spent $232,953 on mailings and billboards in support of Deputy Attorney General Leif Dautch.

Homegrown tech investor billionaire Chris Larsen contributed $50,000 to his own committee to help former Police Commission President Suzy Loftus. And Deputy Alameda County District Attorney Nancy Tung got a $25,000 boost from Oakland attorney Michael Yang to Accountablity Now, Citizens in Support of Nancy Tung.

San Francisco Chronicle columnist Phillip Matier appears Sundays and Wednesdays. Matier can be seen on the KGO-TV morning and evening news and can also be heard on KCBS radio Monday through Friday at 7:50 a.m. and 5:50 p.m. Got a tip? Call 415-777-8815, or email pmatier@sfchronicle.com. Twitter: @philmatier