Governor and Brown Confident; Turnout Low : Politics: Voter apathy lends an air of uncertainty. Only about 12% had gone to polls by midafternoon.

Republican Gov. Pete Wilson and Democrat Kathleen Brown were so confident of winning their primary elections Tuesday that they already had scheduled post-primary victory events to kick off the general election campaign against each other.

Although each enjoyed substantial leads in the final major public opinion polls, there was an air of uncertainty about this election. The official turnout forecast was 5.6 million voters, a record low 39.8% of those registered. Some experts thought voters were more angry than merely apathetic.

By midafternoon, the voter turnout in selected California counties was only 12%, or about 5 percentage points below the percentage at the corresponding time in 1990, the secretary of state’s office said.

Turnout in Los Angeles County was shaping up to be the lowest reported since midday statistics first were kept in 1964, running at 15.7% by 3 p.m., one hour later than the statewide report. The 3 p.m. county figure was nearly two percentage points lower than at the corresponding hour in 1990.

“We may (end the day) even lower than the 37.70% (total) in 1990,” said Marcia Ventura, spokeswoman for the Los Angeles County registrar-recorder. “It may be voter apathy. There may be nothing of interest to the voters on the ballot. It might be that the politicians have not campaigned enough. It’s a difficult one.”

Those voters who did go to the polls also were choosing party nominees for six other statewide offices and two finalists in the nonpartisan contest for state superintendent of public instruction.

Also at stake were nominations for one of California’s two U.S. Senate seats and for 52 seats in the House of Representative, 100 of the 120 seats in the California Legislature, nine ballot measures and a variety of county and other local posts.

The U.S. Senate seat has been held the past two years by Democrat Dianne Feinstein, who won an election to fill the vacancy created when Wilson became governor. Feinstein had no major opposition for the Democratic nomination for a full, six-year term.

The major GOP contenders for the right to face Feinstein in the fall were Rep. Michael Huffington of Santa Barbara and former Rep. William E. Dannemeyer of Fullerton.

But the most attention was focused on the governorship. Wilson, 60, sought the GOP nomination for a second and final term, which he said would cap his political career of more than three decades in elected office--as a state legislator, mayor of San Diego, U.S. senator and governor.

For state Treasurer Brown, 48, victory on Tuesday would mean California Democrats had chosen a woman to lead their state ticket for the second consecutive time and would establish her as a national star of the Democratic Party.

Brown’s margin in public opinion polls narrowed in the final week as her major opponent, state Insurance Commissioner John Garamendi, ran a $500,000 television advertising campaign questioning how tough she would be on criminals since she was personally opposed to capital punishment.

Wilson faced a stronger-than-expected challenge during the primary from Ron Unz, a 32-year-old political unknown at the beginning of the year who spent about $2 million of his own to promote himself as the real Republican running for governor.

Unz, a physicist who became a Silicon Valley computer software entrepreneur, hammered Wilson as a turncoat to the conservative tradition of Ronald Reagan and attacked Wilson’s policies on the budget, taxes, education and crime.

Another wild card in the governor’s race was the late entry in the Democratic primary of state Sen. Tom Hayden, 54, of Santa Monica, the onetime student radical leader who used his low-budget candidacy to promote political and campaign reform. When Hayden announced his plans, he said he had no illusions about winning. But after winning high scores for his performance in the Democrats’ three campaign debates, Hayden began to talk about winning the contest.

The 1994 primary campaign was fought against the backdrop of a California in trouble: The Golden State suffering severe recession, state services strained by illegal immigrants and a public alarmed over violent crime. Since Wilson took office in 1991, California also has been battered by an array of disasters, including the 1992 Los Angeles riots, floods, fires and earthquakes.

With the cachet of the Brown family name and a bi-coastal network of influential supporters, Brown established herself early on as the front-runner. In mid-1993, Brown already had $3.5 million in her campaign treasury and had raised about $10 million by this spring.

Wilson and Garamendi began the campaign in debt and the Hayden and Unz candidacies were not even on the horizon. Wilson also had been taking a pounding in the opinion polls, suffering the lowest job-approval ratings of any governor in modern California political history.

National commentators began writing Wilson’s political obituary and forecasting Brown as his successor.

Brown tried to reinforce this impression by focusing almost exclusively on Wilson, as if the primary election was already behind her. Until the final two weeks of the campaign, she virtually ignored her primary opponents, Garamendi and Hayden. She emphasized her family’s deep roots in California history and their determination to stay in California in spite of adversity.

Meanwhile, Wilson had adopted a simple campaign strategy beginning last summer, as his popularity was inching back to respectability in the polls. He adopted crime and illegal immigration as his key issues and dismissed Brown’s economic attacks by declaring that recovery was under way.

Wilson seized on the “three strikes and you’re out” campaign to impose tough new sentences--up to life in prison--for any criminal convicted of a third felony.

Wilson also proposed a series of controversial restrictions on illegal immigration, including an amendment to the U.S. Constitution that would repeal the present provision that any child born in the United States automatically enjoys U.S. citizenship, even if his parents are in the country illegally.

Wilson ignored his primary foe, Unz--except for a single radio debate--and went after Brown, hoping to soften her up for the fall campaign.

Garamendi had built his cash-poor campaign around what he called “workdays,” in which he toiled side by side with an ordinary California citizen for a few hours in each of the state’s 58 counties.

The experience provided Garamendi with useful speech anecdotes, but he never could afford the sort of media campaign that would make the workday idea connect with voters.

Times staff writer Maria L. La Ganga contributed to this story.