During his nine years in the US Senate, Gary Hart has voted along a liberal, Democratic line with a degree of regularity that has earned him high ratings from labor, women's, environment, and civil rights groups.
Yet the Colorado Democrat, who has sprinted from the back of the pack in the presidential race, is today viewed with wariness among these traditional party constituencies. While he has usually sided with them, several of these groups see flaws in the Gary Hart voting record.
He has voted ''about 80 percent right'' for labor, says Bernard Albert of the Committee on Political Education of the AFL-CIO, ''but there are disturbing gaps.''
Those lapses from the labor line are primarily the Hart votes against providing guaranteed loans to save the Chrysler Corporation and against various plans to protect American workers from foreign competition. Both stands are consistent with Hart themes that the United States should restructure its economy instead of propping up failing industries.
''He's a free-trader in a world where we think free trade is a myth,'' says Mr. Albert, who adds that his office is now preparing a list of Mr. Hart's labor ''weaknesses,'' such as in job safety and his backing of a subminimum wage for youths, which labor opposes. He compares the Coloradan with the AFL-CIO's pick for Democratic nominee, Walter Mondale, who as a Minnesota senator earned a 93 percent pro-labor voting record.
But of more concern than the Hart voting record are his verbal swipes at organized labor as a special interest. ''We wonder why suddenly a member who received $136,000 from labor in 1980 (for his reelection to the Senate) and was endorsed by the AFL (-CIO), and who courted, in the summer of 1983, the endorsement of the AFL, suddenly views us as a political entity with ring around the collar,'' Albert says.
Judy Goldsmith, president of the National Organization for Women, expresses a similar sentiment. ''He has been fundamentally good on our major issues,'' the leader of the women's rights group says. ''What has been troubling us is what he's saying - his attack on special interests.''
''We're troubled by what he is referring to,'' she says, saying that these groups ''really include women, blacks, Hispanics, the poor, and children'' that have legitimate concerns. She adds of the Hart assault on special interests, ''That's a line President Reagan uses.''
Moreover, she scores Hart for declining to sign on to a homosexual-rights bill.
While sympathetic with a number of Democratic causes, Hart has carefully chosen not to be a 100 percenter on behalf of any viewpoint during his Senate career.
He has sometimes exasperated groups who have expected more, especially in the areas of the environment and arms control.
For example, Environmental Action, which has rated all of the candidates, gives the highest marks to Hart.
''He stood out because of his leadership'' in areas such as clean air and pollution, says Francesca Lyman, editor of the group's magazine, who chides him for favoring highway construction while wavering on funding for mass transit in the past.
But the harder-line Friends of the Earth is far from satisfied. Bob Chlopak, director of the group's political-action committee, points out that Hart's League of Conservation Voters rating has slipped in recent years to 66 percent in 1982.
Hart is ''undependable'' on nuclear power issues, according to Mr. Chlopak, whose group opposes all use of nuclear power. The Colorado senator, whose own state has a nuclear power plant, has taken a moderate stand on atomic energy.
''The intangible for us is that Hart is aloof and consistently so,'' says Chlopak, who has endorsed former Vice-President Mondale.
Hart serves on the Senate Environment and Public Works Committee and is known as an environmentalist, but ''he's not that dependable when it comes to carrying amendments to the floor,'' the Friends of the Earth official says.
Nor has Hart been ideologically pure in the eyes of nuclear weapons freeze supporters.
It is typical of his style that he has chosen his own pathway through the national defense debate, devising his own arms control plan, which he called ''STOP,'' instead of jumping on the bandwagon of the freeze movement.
He now cosponsors the nuclear freeze resolution in the Senate, but he has also called for a ''build-down'' proposal that critics say would allow the weapons race to escalate.
''He was late in coming to the freeze,'' charges Jerome Grossman, president of the Boston-based Council for a Livable World, who also criticizes him for not participating in a local freeze referendum in Colorado.
''We also feel that he's shown a willingness to grant increases (4 to 5 percent in real terms) in the military budget that we think is too high already, '' Mr. Grossman says. He argues that Mr. Mondale's experience would help him negotiate with the Soviet Union.
But experts who have helped Hart devise his plans reject that notion. Says Coit Blacker, associate director of the Center for International Security and Arms Control at Stanford University and a one-time Hart staff member, ''Of all the senior American politicians I've ever met, he genuinely understands the problem'' of arms control.
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