BOSTON -- The four men and one woman running for governor of Massachusetts this year are testaments to the inadequacy of political labels.

"Conservative Republican" Steven D. Pierce began in politics ringing doorbells for Lyndon B. Johnson and Edward M. Kennedy.

"Liberal Democrat" Evelyn F. Murphy stayed on the sidelines in the turbulent 1960s while pursuing credentials for a business career.

"Liberal Republican" William F. Weld was the 1980 Massachusetts campaign chairman for Philip M. Crane, the only contender for the GOP presidential nomination who ran to the right of Ronald Reagan.

"Conservative Democrat" John H. Silber traces his political roots back before the Great Society to the maverick liberal Democrats of Texas.

And "Democratic insider" Francis X. Bellotti was far more blunt in his criticism of Gov. Michael S. Dukakis (D) than most of the self-proclaimed "outsiders" in the race -- and spoke his mind when Dukakis was still riding high.

But because image can often dominate reality in this age of media politics, voters are sorting the candidates into convenient stereotypes.

The process is most obvious in the Republican race. Weld, a gangly red-haired patrician of 44, bridles at the Boston news media's insistence that he represents the last, dying breath of the Brahmin tradition in Massachusetts politics. "I know what they're talking about," he said scornfully. "I went to Harvard. I live in Cambridge. So sue me."

In 1980, Weld made a dramatic bolt from liberal Republicanism to support Crane, the Illinois congressman, for president. His explanation: "I'm pretty conservative on economic issues." When Crane crashed, Weld became Reagan's finance chairman in Massachusetts and used that credential to gain appointment as U.S. attorney, where he made a name for himself as an aggressive prosecutor of white-collar crime and was promoted to assistant U.S. attorney general. He drew headlines in 1988 by resigning in protest when he was unable to persuade his boss, Edwin Meese III, to step down as attorney general because of the Wedtech scandal.

Pierce, 40, took a very different route to his gubernatorial bid that he says gives him a visceral understanding of the thousands of blue-collar former Democrats who twice put Massachusetts in the Reagan column.

The son of a self-employed carpenter, Pierce as a teenager "bought the notion that Barry Goldwater was too right wing" and worked for the 1964 Democratic presidential ticket. But even before he went off to Union College and Duke Law School, the slim, bookish young man had decided "the liberal philosophy did not ring true."

He reached Beacon Hill as a freshman representative in 1978. After Dukakis reclaimed the governorship in 1982, Pierce's star began to rise in tandem with the governor's. The more prominent Dukakis became, the more Pierce tried to deflate claims of a "Massachusetts Miracle." Chosen as minority leader in 1987, Pierce was quoted in dozens of press profiles of the Democratic presidential hopeful, warning that "Dukakis has engineered a huge increase in spending, which jeopardizes our fiscal system, and yet the bridges and roads aren't being fixed, the schools aren't being improved and those who really need help aren't getting it."

When the Massachusetts economic crash last year brought an unending crisis in the state budget, Pierce looked like a prophet -- at least to delegates at March's GOP endorsing convention, who voted overwhelmingly for him over Weld.

Before the convention, Weld tried without success to convince the delegates he was a real conservative, flaunting his support for the death penalty and his endorsement of a tax-rollback initiative on the November ballot.

But in ads this month Weld has gone back the other way, arguing that he has a stronger environmental record than Pierce and laying heavy stress on his abortion rights position. He argues that Pierce's antiabortion stance would doom theRepublicans' best chance in 20 years to win the governorship.

On the Democratic side, the candidate strategies have isolated and defined three distinct constituencies that the Democratic Party has had an increasingly hard time keeping together in one coalition.

By age and heritage, Bellotti, 67, has emerged as the candidate of the New Deal Democrats, the labor and ethnic and blue-collar workers, including the biggest chunk of black voters.

Murphy, 50, has become the champion of the reform or "movement" Democrats, including many of the teachers, the feminists and the gay rights advocates.

Challenging both is the Silber, 63, whose caustic criticisms of Democratic orthodoxy have kept the race in constant turmoil. Surveys show Silber speaks mainly to those who, even if registered Democrats, now consider themselves independents. Many of them, like Silber, voted without embarrassment for Reagan and George Bush.

But, as with the Republicans, the reality of the three candidates diverges sharply from the stereotypes.

Few of Silber's supporters probably know that the Boston University president (on leave) started out in the liberal wing of the Texas Democratic Party or that he worked with the lion of that long-suppressed group, former senator Ralph Yarborough (D-Tex.), on such Great Society programs as Head Start and bilingual education.

In some respects, Silber remains an ardent apostle of activist government. He advocates state-funded preschool programs for every Massachusetts child and says that when a welfare mother has a second illegitimate child, the state should intervene and provide foster home care for those children.

Like both his "liberal" rivals, Silber also is opposed to the tax-rollback initiative supported by Pierce and Weld.

But these aspects of Silber's candidacy have received scant attention amid media coverage that has been driven by Silber statements verbally shredding some sacred symbols of conventional Democratic dogma. Rather than promise increased benefits to the elderly, for example, he has said that rationing of health services is inevitable, and those in the final stages of life should be well down the list. "When you've had a long life and you're ripe," he said, "then it's time to go."

Other statements -- equally pungent -- have brought pained reactions from Jews, blacks, Hispanics, Asian immigrants, feminists, teachers, state employees and others in the Democratic coalition. Bellotti and Murphy suggest that Silber is really not a Democrat at all.

He insists that he is -- and that he's never wavered since, as a 10-year-old Depression youth, he told his impoverished architect father, a Republican precinct committeeman in San Antonio, that he ought to recognize that "everything good that's happened to us happened because of President Roosevelt." Silber says his disillusionment began "with the student revolution" of the 1960s and crested with the "perfidy" of Sen. Eugene McCarthy in refusing to support Vice President Hubert H. Humphrey, a Silber hero, after the 1968 Democratic National Convention.

Except for Jimmy Carter, who briefly kindled his hopes, Silber found all the recent Democratic presidential nominees, including Dukakis, guilty of "knee-jerk capitulation to people who would sell out America."

With an angry, disillusioned electorate, Silber's message has stirred a strong response -- both positive and negative. But he has had difficulty undercutting Bellotti, whose New Deal credentials are there for all to see.

Born in Dorchester, the only child of a badly wounded and chronically ill World War I veteran and a school employee-government clerk mother, Bellotti joined the Navy in World War II, went through Tufts and Boston College Law School on the G.I. Bill, and came away believing that "I could not have lived or ever have become educated without . . . the programs Democrats had passed."

In 1964, as lieutenant governor, he challenged and defeated Gov. Endicott Peabody in the Democratic primary, then lost a close race in November, the first of many times when, in Bellotti's view, opponents played on ethnic prejudice against Italian Americans by attempting to link him to underworld influences.

Ten years passed before Bellotti won public office again as attorney general. It is his 12-year activist record in that office, on consumer, environmental and civil liberties cases, as well as bribery and kickback prosecutions of public officials, that Bellotti cites to answer Silber's TV ads charging his "corruption record" is weak and Murphy's suggestions that he is a relic of insider Democratic politics of the past.

In fact, Bellotti has been a boat-rocker, from the time a quarter-century ago when he challenged Peabody down to 1986, when he told the Democratic state convention that was about to endorse a then-dominant Dukakis for a third term that the party's future was in jeopardy because Democrats had "stopped talking to all of the people."

In an interview, Bellotti made it clear where his political heart lies. "I'm for abortion rights and gay rights," he said, "but there are a lot of people who have to go to work every day at pretty tough jobs . . . and they want to feel that someone cares about them and appreciates them. . . . They believe they've been paying for all these programs and not benefiting from them . . . and they've got a point."

Murphy, by contrast, seems much more at home in the suburban living rooms where Dukakis found much of his support. Insiders know the irony of her position: As lieutenant governor the last four years, she often got stiff-arm treatment by Dukakis aides who bad-mouthed her abilities and froze her out of achieving influence or power at their expense. But as the only Democratic gubernatorial candidate now in public office and as the person who was at least nominally No. 2 in the Dukakis administration, she inherited the task of defending what has become an overwhelmingly unpopular record.

She has done what she can with the assignment. In a speech at Harvard last April that her campaign urges reporters to examine, she declared: "I am here to say that I am a liberal. . . . I am here to say that liberalism represents the best our party has to offer." She could understand "why some taxpayers are angry," but she vowed not to use "anti-government buzzwords that pander to cynicism." But when Dukakis scheduled a trip to Europe this week, Murphy leaked word that as acting governor, she would make personnel and program cuts he had rejected. The angry confrontation between Murphy and the governor has dominated the headlines in the last few days.

Unlike her rivals, she had endorsed the $1.6 billion tax package passed by the legislature earlier this year. But for this campaign, Murphy has chosen to place much more emphasis on her opposition to the death penalty and her support for completely unrestricted abortion rights. (Silber and Bellotti support the death penalty in a limited number of cases; both endorse the Supreme Court's Roe v. Wade decision that legalized abortion but authorized limiting abortions in the final trimester.)

Although Murphy has been positioned as the most liberal in the race, her background was "apolitical," she says. The daughter of a career Army officer, she moved frequently and spent the turbulent '60s in getting her academic credentials, including a doctorate in economics from Duke, and launching an economic consulting firm.

Although Murphy did not work in Dukakis's 1974 campaign and had only met him once, she became secretary of environmental affairs for reasons she does not romanticize. "Michael had pledged to appoint four women to his Cabinet, and he ran out of time and candidates," she recalled.

Her record in the post won her plaudits from environmental groups and considerable criticism from business, a gulf she tried to bridge when she served as a notably cautious secretary of economic affairs from 1983 through 1986. "I am a no-nonsense, business economist," she said in an interview. But that is clearly not what is drawing the feminist and liberal activist support to Murphy.

At this point, Murphy and Weld -- supposedly the most liberal candidates in the two parties -- are the long shots to survive the Sept. 18 primary. But whoever becomes Massachusetts's next governor is likely -- given the record -- to be a far cry from the caricatured candidate the voters are seeing now.

Staff researcher Bruce Brown contributed to this report.