California Lieutenant Governor Gavin Newsom. Photograph by Jae C. Hong/AP

On Wednesday morning, little more than three months after California’s voters reëlected Governor Jerry Brown for another four years, Gavin Newsom, the lieutenant governor and former mayor of San Francisco, became the first person to declare his intention to take Brown’s place when he reaches the end of his final term at the start of 2019. “When Californians see something we truly believe in, we say so and act accordingly—without evasiveness or equivocation,” Newsom wrote in a letter to supporters, announcing that he is forming an official campaign committee to seek the governorship.

The announcement came not longer after Jeb Bush, the former governor of Florida and the first major candidate to declare that he will consider running for President in 2016, was experiencing one of the downsides of entering a race on the early side: it leaves you more time to screw up. Over the past few days, Bush’s political-action committee released e-mails that included some Floridians’ social-security numbers, and its newly hired chief technology officer had been forced to resign over several comments he had made in the past, including tweets that referred to women as sluts.

In a phone call on Wednesday afternoon, Newsom acknowledged the potential pitfalls of his decision—he joked that he was giving opposition researchers more time to dig up dirt—but said that, rather than quietly open a fund-raising account that is purportedly meant to raise money for some other race, when everyone knows that he wants to be governor, he preferred to be forthcoming about his intentions. “Love me or hate me, at least you know where I stand,” Newsom said. “You can be coy, or you can be candid—I’d rather be candid and let people judge that. Obviously there’s not much precedent for jumping out this early, so it’s ripe for critique.” Newsom acknowledged, too, that announcing so soon lets him get an early start on raising money and articulating a platform. “So often, time and its constraints get in the way of good decision-making—like, ‘We have to get this policy paper out this week even though it might not be vetted, might not have the substance it otherwise would if we had taken more time.’ ” He added, “If I waited two years, it’d be all about raising money, raising money, raising money.” The Democratic establishment in California might be eager, too, to anoint a frontrunner early on; it’s unclear who will run against Newsom, though the state treasurer, John Chiang, and both the previous and current mayors of Los Angeles, Antonio Villaraigosa and Eric Garcetti, all Democrats, have been named as potential candidates, among others.

From 2004 to 2011, when Newsom was mayor of San Francisco, he had—and sometimes nurtured—a spectacularly high profile. He issued licenses for same-sex marriages, in defiance of state law at the time, and instituted universal healthcare for city residents. He also slept with a top aide’s wife, went into rehab to address what he called “problems with alcohol,” and supported controversial real-estate development and homelessness programs. Nevertheless, Newsom’s legacy as mayor is one seen as having been substantial, if not universally admired. But he has barely been in the news since his election, in 2010, as lieutenant governor—a position that, he readily acknowledges, isn’t particularly powerful. “There are constraints to this office,” he told me. “You serve in these formal roles”—he sits on the University of California’s Board of Regents and on the State Lands Commission, among other positions—“and by the way those are very significant roles, they’re important, but beyond that you’re not negotiating labor contracts, you’re not signing executive orders, vetoing or approving legislation, or participating in that legislative process.” In California, the position is mostly seen as a relic of a time when, if the governor travelled out of state, it was important to have a backup in Sacramento to do business for him; now that governors can easily take care of state business even while travelling, it’s sometimes unclear what, exactly, the lieutenant governor is supposed to do.

Newsom was made aware of the limits of the job early in his tenure, in 2011, when he decided to focus on economic development, even publishing a report, with input from the Brookings Institution and the McKinsey Global Institute, on how California should change its economic policies to better support growth. But Brown—the person in the best position to turn those recommendations into policies—didn’t seem much interested in adopting Newsom’s ideas, on the economy or on other matters. He cared more about balancing the state’s budget; plus, the two men, who ran against each other ahead of the 2010 gubernatorial primary, before Newsom dropped out and sought the lieutenant governorship instead, aren’t said to have a particularly warm relationship, and Newsom’s economic-development report was interpreted, in some quarters, as a challenge to Brown.

Since then, Newsom seems to have settled for quieter moves—opposing proposed tuition hikes at the University of California, for example—while biding his time. When he ran for reëlection, in 2014, the Los Angeles Times editorial board preceded its endorsement of him by calling the position a “notoriously do-little job.” The board wrote, “Being lieutenant governor mostly serves as a perch for gubernatorial candidates-in-waiting. Nevertheless, voters are asked every four years to choose among the aspirants, so here goes.” It’s little wonder, then, that Newsom—who, love him or hate him, did more as mayor of San Francisco than most—is eager to start doing something again.

By the time 2018 comes around, California will have changed tremendously since 2009, the last time Newsom campaigned for governor. In some ways, his race, and the way Californians react to it, will be a proxy for that evolution. Some of those changes bode well for Newsom. The last time he ran for governor, he recalls, even his friends questioned whether his gay-marriage stunt, in 2004, would hurt him. In 2008, after all, Californians had passed the Proposition 8 ballot measure, which defined marriage as being between a man and a woman. It wasn’t until 2010—after Newsom had dropped his bid for governor—that the percentage of Californians supporting gay marriage surpassed the percentage opposing it, and it wasn’t until 2013 that a U.S. Supreme Court ruling allowed the legalization of gay marriage in the state. “His bet, and it was a courageous bet, when he was mayor, was that supporting gay rights would not be a career killer—he was right,” Bruce Cain, a political-science professor at Stanford University and a longtime observer of California politics, told me. “It’s going to be something that’s he’s going to be able to rightfully tout.” The idea of universal healthcare, once seen as radical, has also become more accepted, particularly in California, since the passage of the Affordable Care Act.

But the California electorate is also changing in ways that may not favor Newsom. The four counties that are expected to see the greatest population growth, in absolute numbers, from 2010 to 2020, are all in Southern California—Los Angeles, Riverside, San Diego, and Orange. The differences among the California electorate are blurry for those on the outside—they look like varying shades of blue—but they’re real; Democratic voters in some parts of the south, for instance, describe themselves as “conservative” at much higher rates than those in the Bay Area do. Southern Californians can also be mystified by—and resentful of—Silicon Valley and its solutionist ethos. Though Newsom has now won two statewide races, he is perceived as a distinctly San Francisco type, with the gel-enabled good looks, and the breezy confidence—in himself and in the power of technology to solve problems—of a venture capitalist. In 2013, he wrote a book called “Citizenville: How to Take the Town Square Digital and Reinvent Government,” which, as George Packer wrote, in a 2013 article about Silicon Valley’s politics, includes lines like: “What if you could create competition among city services . . . through a kind of government Yelp? Then we’d be on to something.” Newsom is also, of course, white, in a state with a growing non-white population; last year, the number of Latinos in the state was estimated to have surpassed the number of white non-Latinos.