Newton: What now in the mayor’s race?

The first round of the mayoral election ended Tuesday much the way it began, with Controller Wendy Greuel and Councilman Eric Garcetti fighting for the lead while facing the complicated task of defining themselves to voters and assembling a majority in an exceptionally diverse city.

Both candidates have logical routes forward for the runoff, and both can look to historical precedent for proof they might win.

Greuel can take heart from the election of 2001, when Jim Hahn came in second in the first round of the election but rebounded to victory in the runoff after moderates who’d voted for other candidates in the first round picked him over Antonio Villaraigosa. Look for Greuel to start painting Garcetti as a radical while casting herself as a moderate.

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For Garcetti, the 2005 election is a more appealing model. That time, liberals and moderates banded around Villaraigosa and put him into office, ousting Hahn.

Key to the Greuel strategy is picking up voters who cast their ballots Tuesday for Kevin James, a moderate Republican who ran into the glass ceiling that blocks most GOP members from winning in this city: There simply aren’t enough Republicans left here to carry a candidate to victory. In a close election, however, Republicans can provide an advantage to the more moderate Democrat, and in the May election, Greuel seems more likely to get those votes than Garcetti.

Bob Hertzberg, a former speaker of the Assembly and former candidate for mayor, supports Greuel, and he, like many I’ve spoken to in recent days, sees the James votes as potentially pivotal. Hertzberg said he figures about one-third of James’ backers will simply stay home in May. That leaves two-thirds, and Hertzberg predicts that Greuel, with her background as controller giving her some outsider status in this contest, is positioned to pick up the lion’s share of those.

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That said, it’s by no means certain that she’ll win, or even that she’ll pick up the bulk of James’ votes. Expect to hear Garcetti continue to harp on Greuel’s support from the International Brotherhood of Electrical Workers, the union that represents most DWP employees. That union’s heavy spending on her behalf, Garcetti argues, makes her beholden to the special interests that dominate City Hall. If that message resonates with conservatives and drives them to Garcetti, he could pick Greuel’s pocket.

Moreover, James himself is a wild card. I ran into him on election night, and he warned that he’s not sure who, if anyone, he might back in the runoff. One particular concern he mentioned: He doesn’t want Brian D’Arcy, the head of the IBEW, to have outsized influence at City Hall. That’s a warning shot at Greuel.

For his part, Garcetti needs an energized liberal base to turn out young voters, whom polls have shown support him. He also needs strong support from Latinos, and to claim his share of the voters who backed the other significant finisher in Tuesday’s vote, Councilwoman Jan Perry.

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Perry’s base may be the hardest to parse, as it included several threads. There were voters who were unhappy with City Hall and thus admired her scrappiness and candor. There were downtown interests. And there were African Americans, who make up a significant portion of her council district. Perry’s endorsement will be eagerly sought, and most observers think she’ll back Garcetti. But whether her endorsement can actually deliver her bifurcated base to the candidate she endorses is still a question.

All predictions based on history should be qualified by the one clear lesson of this race so far: Traditional bases of power in Los Angeles are less solid than they once were. When Tom Bradley ran for mayor, blacks overwhelmingly supported him against any opponent. When Villaraigosa sought the office, he could count on the vast majority of Latino votes. In this race, the National Organization for Women backed Garcetti over two women, while many leading Latino officials backed a white woman, Greuel, even though Garcetti is partly of Mexican heritage and speaks fluent Spanish. Some black leaders supported Perry, who is African American, but Council President Herb Wesson, the first African American ever to hold that post, did not.

In one sense, that’s a sign of civic health and progress. It’s heartening not to be able to simply tally up the city’s voter registration by interest group and predict a winner. But it also makes the coming campaign more fluid and unpredictable.

“The lines are not as clear as they have been before,” noted Raphael Sonenshein, director of the Edmund G. “Pat” Brown Institute of Public Affairs at Cal State Los Angeles. “Nobody’s base is all that solid.”

For those frustrated by the shallowness and evasiveness of the campaign so far — which is to say, anyone who’s followed it closely — the consolation may be that an evenly divided city with large batches of undecided voters should draw out the differences between Garcetti and Greuel. At last, perhaps, we will get them to envision a new physical Los Angeles. Maybe they will move beyond cliches and tell us how they would solve the city’s budgetary crises or how they would govern across racial and class divides.

That would make this a campaign worthy of the effort — and perhaps it would persuade more than the paltry one-fifth of registered voters who turned out Tuesday to vote in May.

Jim Newton’s latest book is “Eisenhower: The White House Years.” Reach him at jim.newton@latimes.com or follow him on Twitter: @newton_jim.