As he finishes his first year as California governor, there’s one important metric on which the famously data-driven Gavin Newsom can breathe easy: his approval rating.

In a November poll from the Public Policy Institute, 48% of likely voters said they approved of the job Newsom was doing as governor.

There’s plenty of room for improvement in Newsom’s ratings, of course, but they actually represent an increase from his inauguration, when he had a 43% approval rating. The poll also suggests that the strange, long-shot recall campaigns against him have little chance of succeeding. If anything, these attempts may only result in the further marginalization of the California GOP, which has endorsed them.

That’s the very good news for Newsom at the end of a tumultuous first year. His strategy of offering stiff resistance to President Trump while taking an active role in every big state issue, from the PG&E bankruptcy to early childhood education, seems to be resonating with voters.

The question is, how long can that last?

Many of the biggest challenges facing California, like a historic crisis in housing and homelessness, are only intensifying, even as he has made them a priority.

Newsom promised “a Marshall Plan for affordable housing” during his inauguration speech. He vowed to build 3.5 million new housing units by 2025.

However, a July report from the California Department of Finance showed that California had built 11% fewer units during the first half of 2019 than the state did during that same period in 2018.

The reasons for the housing shortage are many — a statewide pattern of under-building housing that stretches back decades, current high costs for land and construction, a tax code that disincentivizes local governments from increasing housing production, and wealthy cities that remain defiantly against adding more places for people to live.

Housing costs are driving away the state’s middle class and affecting its economic growth. It’s also spilled over into a homelessness crisis that’s paralyzed California’s cities and earned the wrath of the Trump administration. Newsom’s leadership on homelessness has helped deliver billions in public investment, new collaboration with the private sector, elevated attention to mental health issues, rent control legislation and assorted other regulatory reforms.

The new energy and attention is welcome, but the challenge will be to maintain that momentum in 2020.

The interlinked tasks of combating wildfires and managing the havoc of a bankrupt PG&E is another huge challenge with serious potential pitfalls for Newsom.

In July, Newsom named Marybel Batjer as the new president of the California Public Utilities Commission. Batjer, a savvy government veteran with a reputation for bringing positive changes to entrenched bureaucracies, has already guided the the CPUC toward a new tone with PG&E. PG&E was accustomed to lax enforcement from this agency, and Batjer has met the company with demands for immediate corrective actions and investigations into the power shut-offs that threw Northern California into chaos this year.

In December, Newsom scuttled PG&E’s $13.5 billion plan to resolve its bankruptcy with victims’ attorneys, declaring — correctly — that it fell short on necessary goverance reforms to protect the state of California.

Those were two wise choices Newsom made on the issue in 2019. But next year will bring new challenges, new blackouts, and the possibility of new and even more dreadful wildfires.

Energy failures were a driving force behind the recall of previous California Gov. Gray Davis — Newsom will need to pay close attention if he doesn’t want to face a similar evaporation of public approval.

Many observers have negatively contrasted Newsom’s style of tackling every issue with that of his notoriously focused predecessor, Jerry Brown.

It’s true that, in his second year, Newsom should hone his governing style by showing Californians which issues he believes matter the most for the future of the state. But it’s also true that Newsom faces different challenges than Brown did, and will be judged accordingly.

California voters care dearly about standing up to a hostile federal administration — but as the polls show, they’re also deeply worried about homelessness, jobs and housing affordability. Being a successful governor in 2020 will require Newsom to make headway on them all.

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