The ambitious lawyer with a reformer's zeal was elected governor of California at an unusually young age. His father had also been a successful politician, but he disdained the old man and turned the state in new directions, winning re-election before jumping to a U.S. Senate seat.

Sound familiar? This thumbnail biography is that of Hiram Johnson, California's controversial governor and senator from 1911 to 1945. It has a melancholy ending, according to Michael Barone, publisher of the Alamanac of American Politics, for Johnson in Washington became: "A loner, unable to influence his colleagues, a bitter and unpleasant man whose nation seemed little interested in his once sparkingly reformist ideas."

At first, this sounds like the past and what might be the future of California's Gov. Edmund G. Brown Jr. Despite a 41 percent unfavorable job rating, Brown is far ahead in his race for the Democratic nomination for the U.S. Senate, the latest of his political resurrections which may this time take him to Washington, if not to the White House as previously planned.

Despite a disastrous 1980 presidential campaign and a painful brush with an infestation of the Mediterranean fruit fly, Brown, 43, inspires more conversation--and more respect by his opponents--than any other American politician of his generation. Graced with excellent political instincts and a restless intellect, he has in the depths of unpopularity found another lively issue--the American technological crisis--that may bring him back up in the polls. Only the suspicion and envy that follow his ideological agility stand in the way of his testing Barone's gloomy prediction of Brown's future on the Potomac.

After years of identifying himself with tax cuts and austerity, making the best of an era of limits, Brown has struck out on a new path, dramatized by an optimistic "state of the state" speech last month in which he said "the only viable path to continued prosperity is through the increased commitment to greater knowledge and invention."

He called for more money for scientific education to fend off the Japanese and Soviet challenge. "Electronics, computers, satellites, biotechnology, robotics--these are no longer dreams," he said, in a speech praised by some former critics. "They are the driving imperative that is restructuring the world economy."

Riding in his beat-up 1974 blue Plymouth to a speech at a Torrance job training program, Brown carefully underlined his agreement with President Reagan's "general thrust toward more savings and investment."

Brown appears to realize how popular his predecessor as governor still is in California. But he added: "I don't see him realizing the need for the government to play a more active role to absorb the shocks in moving to higher savings." To Brown, this includes providing more job training and social safety nets to catch those whose livelihoods collapse in the reform of the economy and reductions in spending.

"I hate to tell you, I think he's again on the top of a very hot issue," said Ted Bruinsma, the California businessman who is one of eight Republicans vying for the right to meet Brown in the general election. His Republican and Democratic adversaries do not challenge Brown's logic, but complain that his own budget cuts shortchanged the California education system he now pledges to save.

Fresno mayor Dan Whitehurst, 33, one of Brown's two leading opponents for the Democratic nomination, spoke of the governor's "resourceful intelligence, facility with words and issues, his political instincts."

"In terms of his abilities as a politician, he's an artful guy," Whitehurst said. The other leading Democratic contender, state Sen. Paul Carpenter, 53, agrees with Whitehurst that Brown himself remains the focus of the campaign. "I find on the grass-roots level people only want to talk about why he would do such crazy things" as his initial opposition to aerial spraying of the Medfly and his sudden turnabout on cutting real estate taxes.

Carpenter and Whitehurst are focusing on Brown's widely perceived opportunism and aloofness. Each has moved up slightly in the polls, although Carpenter still stands at only 13 per cent and Whitehurst at 9 per cent in a January survey by Mervin Field's California Poll, which showed Brown with 51 per cent. The governor is not expected to have much trouble with other announced candidates, including San Diego white supremicist Tom Metzger and Los Angeles political consultant William Wertz, an adviser to conspiracy theorist and former presidential candidate Lyndon LaRouche. State Controller Ken Cory appears to be shying away from the race and novelist Gore Vidal, another possible contender, has yet to declare himself.

The Republicans most likely to win their party's nomination all solidly thump him in the current polls, however. The Republican frontrunner, Rep. Barry Goldwater Jr., beat Brown 55 to 38 per cent in the January California Poll, and two other Republican contenders, Rep. Paul N. (Pete) McCloskey and San Diego Mayor Pete Wilson, led him by about the same margin.

Brown did not profit from the frank remarks of his new chief of staff, B.T. Collins, to a Los Angeles Times reporter: "He's out in Uranus half the time--thinking. Ten people with real problems can be waiting to see him, and he'll be off in a back room somewhere reading a g-------d book." But he also won some admiration for having the self-confidence to hire a self-confessed Republican like Collins in the first place, and keep him on after his indiscretions.

Carpenter, who has raised only $252,758 as of Dec. 31 compared to Brown's nearly $1.9 million, is a conservative Democrat from Orange County who has attacked Brown's handling of the Medfly, his appointment of liberal judges and his efforts to stop construction of nuclear power plants. He supports much of the Reagan economic policy but faults it for not gaining more cooperation from labor unions and the Japanese. Like Brown, he calls for more money for high technology research and development.

Whitehurst has raised only $243,453 as of Dec. 31, and spent almost all of that. Like Carpenter, he argues that a campaign chest the size of Brown's is useful only if a candidate needs more name recognition, which Brown doesn't, particularly when so many who recognize Brown don't like him.

Whitehurst, more liberal than Carpenter, said he and Brown would probably vote the same on many issues, "but I take public office seriously." He said he would do better working with fellow Democrats and suggested Brown would approach the Senate as just another media event.

Brown's unfavorable job rating has grown from 11 per cent in 1976 to 41 per cent today. "After eight years, I think that people get tired of you," Brown said.

How can he counter that trend? "By confronting new challenges which the federal office opens up," he said. "The people are taking my ideas very seriously." But won't his image of inconsistency and opportunism, which has helped all his likely Republican opponents, overtake him in the polls and do him in?

"We'll find out," Brown said.