Back in August, when Lt. Gov. Madeleine Kunin (D) spoke at a luncheon of the Women's Network here, she was asked how she had "evolved as a politician."

"I'm still evolving," she said, tossing back her head and laughing. But it was no joke. As Kunin's race for governor has gone on, it has become clear to almost everyone in Vermont that, win or lose, she has evolved into one of the state's most promising politicians.

Chances are, she will lose to Gov. Richard A. Snelling (R), the three-term incumbent. Polls show the 55-year-old Snelling, a successful businessman, has parlayed his reputation as a competent manager and the publicity he gained last year as chairman of the National Governors Association into a comfortable lead.

Although Kunin, 49, has developed support from some women that crosses party lines, the prevailing attitude seems to be that expressed by Burlington cab driver Tom Matthews.

"She's charismatic and very able, but I'm going to vote for Snelling again," he said. "I like things orderly, and he's got this state government really well organized. He's a businessman who squeezes the dollar hard, but he also knows where it's important to spend some money. So why change a good thing?"

Snelling, who faced a woman in an earlier race, is unfazed.

"I have every reason to believe and no reason to disbelieve," he said, in his characteristically ornate style, "the outcome will be very close to that of my last campaign," when he won 61 percent of the votes.

Kunin, however, said last week she is "highly encouraged" by the response she gets campaigning and by the steady flow of funds from some 2,000 contributors into a campaign treasury that has passed the $175,000 mark -- a healthy sum for this small state.

A native of Switzerland, she came to America with her widowed mother, worked her way through the University of Massachusetts, received a graduate degree in journalism from Columbia University and moved to Vermont in 1957 to work on the Burlington Free Press.

Married to a University of Vermont professor of medicine and the mother of four, she became active in the League of Women Voters and other voluntary groups.

"I looked at issues, not the processes for deciding issues," she said here in August.

But after winning a seat in the Vermont legislature in 1972, "I realized that if you are concerned about programs, you have to follow them through the budget process."

Gaining a seat on the House Appropriations Committee and, in her third term, becoming its first woman chairman, she said, "I learned not to be intimidated by expertise. I learned that numbers are just another language and that budget decisions are basically value judgments, and you're just as capable of making them as anyone."

When she decided, after four years as lieutenant governor, to bid for the top job, Kunin's first concern was to make her campaign "credible." That meant building an early war chest to scare off intra-party challengers, hiring professional campaign consultants, and laying out detailed programs for agriculture, economic development and law enforcement--areas of policy where her credentials were suspect.

But she was notably diffident about criticizing Snelling or his record until, she said the other day, "it became clear about Labor Day there had to be a different tempo. A lot of people were caught in the basic dilemma of seeing two qualified people and not knowing which to support. So we started spelling out the differences."

In speeches and ads, she criticized the incumbent for permitting "secret" shipments of nuclear wastes through the state, for condoning a run-up in utility rates, and for opposing the nuclear freeze.

Asked about her new aggressive tactics, Kunin said last week, "It's a question again of evolving. We made a joint appearance the day after the [Sept. 14] primary, and I felt reinforced by facing him at the podium and realizing I could do well. That's a psychological step you go through, and the confidence it gave me has been significant."