Reich, 54, proved his liberal bona fides as President Clinton's first secretary of labor, arguing unsuccessfully for federal spending to jumpstart the then- foundering economy and leading the left-leaning faction of Clinton's first Cabinet.

So more than a few readers might have choked on their cereal when they saw Reich's name attached to a recent opinion piece in The Wall Street Journal supporting school vouchers, an idea backed by George W. Bush and many conservatives but anathema to Al Gore and the Democratic Party.

Now, Reich finds himself ''the liberal poster child for the pro-voucher movement'' as he put it. The e-mail messages and letters have been pouring in: about 500 at last count, some from mayors interested in trying out Reich's idea - a system under which the poorest families would get the largest vouchers. Reich's pro-voucher story, in the current issue of The American Prospect, has only increased the flow.

But he is hardly the first liberal to break ranks and give vouchers a second look. More and more, the voucher issue is defying the normal political classifications, blurring the line between Democrats and Republicans, liberals and conservatives.

Democratic politicians launched Milwaukee's voucher program, the nation's oldest, a decade ago. A former New York congressman, Floyd Flake, and the former Atlanta mayor, Andrew Young, are prominent supporters of the idea, as are many African-American and Hispanic community leaders who are loyal Democrats but who are desperate to get children out of failing public schools.

''It's a conservative idea if you look only at the voucher side of it,'' said Reich, who got his start in national politics organizing against the Vietnam War. ''It's a liberal idea if you look at getting more resources behind poor kids, and creating incentives so rich schools do everything they can to attract those children.''

At a time of intense interest in education, vouchers are a hot topic. Bush's education proposal includes a voucher plan - though he avoids calling it that because the term is so divisive. Vouchers are on the ballot in Michigan and California. And a recent Harvard study suggesting that vouchers boosted academic achievement among African-American children attracted widespread media attention. (Other researchers have found little or no gain.)

The basic concept is simple: Under a voucher program, the government gives public education money directly to families, in the form of vouchers, instead of to schools. Rather than being assigned to a particular public school, families can use the voucher to pay for tuition at any school - public or private. In addition to Milwaukee, voucher programs are in place in Cleveland and Florida.

Supporters say vouchers free children from failing schools and create competition that makes all schools better. They say vouchers give all families choices that only wealthy families have now.

Opponents say vouchers drain money from public schools, isolate the most troublesome students, and make struggling schools even worse. They question the constitutionality of giving public money to private religious schools, and argue that if private schools perform better than public ones, it's largely because they can admit and expel whomever they want.

''Vouchers have been like abortion and communism - you're either for or against,'' Reich said. ''As a result all the interesting questions have been submerged: Should children have some choice? And how much choice and under what circumstances?''

He emphasizes that he is adamantly opposed to any program that gives vouchers of the same size to all families. Such a system, he says, would do nothing to improve the socioeconomic segregation that has created ''scandalous'' inequalities in education. Instead, he advocates a voucher system under which poorer children would get the most money.

On average, per-pupil spending in the United States is between $6,000 and $7,000 a year. Under Reich's proposal, a child from America's poorest 20 percent of families would receive a voucher worth $10,000 to $12,000, while children from families in the next quintile would get $8,000 to $10,000. Students from the wealthiest families would get vouchers of between $2,000 and $4,000.

Such a system would have several positive effects, Reich said. First, it would provide an infusion of money to the nation's poorest public schools, allowing them to hire better teachers, buy supplies, and upgrade their physical plants. It also would create a free-market incentive for failing public schools to get better, to attract students - and vouchers - that might otherwise go to competing schools.

A graduated voucher system also would create an incentive for private schools and high-quality suburban public schools to recruit low-income students. It might even be worthwhile for some suburban schools to pay to transport children from the cities.

At first blush, Reich's voucher plan is fundamentally conservative, in that it relies on competition and the free market. But on closer inspection, he says, it's in line with his liberal philosophy.

''It's liberal bordering on radical,'' said Reich, whose children attended Cambridge public schools. ''It fundamentally redistributes educational resources and energies to blue-collar and poor families in ways that the present system does not.''

Compared with other voucher proponents, Reich would place tighter restrictions on participating private schools, requiring that they have open admissions policies and that they not expel students for academic reasons. Reich's plan would force private schools to meet certain curriculum guidelines, and would exclude religious schools, to avoid any constitutional problems.

The Massachusetts state Board of Education chairman, James A. Peyser, a strong voucher proponent who argued his case in a recent debate at Brandeis, said it makes sense to offer vouchers of different value - but not based on income. Peyser suggests that students who cost more to educate, such as special education students and those with limited English proficiency, should get the bigger vouchers.

Peyser, who noted that most existing voucher programs focus on low-income children anyway, also cautioned against burdening private schools with too much regulation.

''We have to be extremely careful about using vouchers to co-opt the private sector,'' he said. ''It's unbelievable to me that there's this belief that our problems with public education can be resolved be making private schools more like public schools.''

Reich says he's now in an ''academic provocateur'' mode, rather than a policy-making one. Nevertheless, he said he'd be willing to help any local or state official interested in implementing his plan.

''I think there's the possibility here of a coalition of conservatives who want more choice and liberals who want more money,'' Reich said as he dashed off to an academic lunch focusing on his idea.

''Otherwise, we're simply stuck in the mud.''

© Copyright 2000 Globe Newspaper Company.

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