In gambling terms, it sounds like the ultimate sure bet. Players need only put down $3,000 when they have a newborn baby. The prize, paid off 18 years later, is four years of tuition at any of 15 public colleges and universities.

It is a novel idea, totally untested and still wrought with unanswered questions. But in Michigan, where the escalating cost of higher education has become a central issue in state political campaigns, the idea seems to have taken on a life of its own, with an election-minded legislature racing toward final approval.

The proposal, the brainchild of Gov. James J. Blanchard (D), is known as BEST, for Baccalaureate Education System Trust. It rests on a simple assumption: that the state can invest a relatively small amount so wisely that it will more than pay for cost of four years in college by the time the child reaches college age.

The Michigan proposal has attracted intense interest from other states, as steadily rising tuition costs have led to calls across the country for some form of tuition cost containment. Michigan's state treasurer, Robert Bowman, estimates that 31 states have contacted his office asking for details. "If imitation is the sincerest form of flattery," he said, "then we ought to be flattered."

The proposal passed the state's Democratic-controlled House by a lopsided 89-to-11 margin, and 30 of 38 members of the Republican-controlled Senate have signed on as cosponsors, according to Sen. Patrick McCollough, a Democrat who is spearheading the effort. "Both sides agree it's a great idea," he said.

Public praises for the program, and its seemingly unstoppable political momentum, have all but drowned out the few remaining voices urging caution, as the state appears set to embark on an uncertain experiment that could alter the course of its higher education financing for the next century.

"You can't have major policy like this passed just because it's an election year," said state Senate Majority Leader John Engler, who complained that the proposal is being "railroaded" by the governor and the House.

"No one wants to appear to be against paying for your child's education," said Patrick Anderson, economic adviser to Republican gubernatorial candidate Richard Chrysler.

"The governor is fooling people into believing that he's got something that's too good to be true, and it is in fact too good to be true," Anderson said. "No one knows what the cost of an education 18 years from now will be. And no one knows what investments will do over 18 years."

There are many unanswered questions. What happens if investments fall short? What if tuition escalates higher than projected because of an unexpected factor, such as the oil shock of the 1970s? Will taxpayers 18 years from now be forced to make up any shortfall? Will the Internal Revenue Service agree not to force parents to pay taxes on the money 18 years from now? Does the plan discriminate against poor parents who may not be able to afford the initial investment? Will colleges lose their incentive to keep costs down?

For many of these questions, supporters prefer to defer the answers to a special new public authority that would be created to administer the program.

The complex plan would work like this: Parents of children up to the age of 14 years could participate. The investment for newborns would be about $3,000, and the amount required to invest would increase with the age of the child.

Currently, tuition at Michigan's 15 state-supported schools averages about $2,000-a-year. For a baby born this year -- the first year of eligibility if the bill passes -- tuition by the time the baby turns 18 in the year 2004 will be $23,000 for four years, according to estimates.

The state has been enjoying a relatively high return on investments, 24 percent last year, according to officials. At those rates, the $3,000 invested now would more than cover that projected tuition bill.

There are also various "payment plans" proposed for parents who cannot invest the full sum at one time. There is the annual plan, the biweekly plan and even a plan for payroll deductions.

If the child decides not to attend college or dies before reaching 18, the parents could receive a full refund, with at least some interest (administrative costs would be subtracted). If the child decides to attend a private school instead of one of the state public schools, the state will give the parents the amount of money accumulated over the life of the investment to apply to the private school tuition.

The plan has become less an education debate and more of a referendum on Blanchard, a popular governor heavily favored for reelection. Said Debra Townsend, press secretary to Senate Republicans: "It sells really well, it's got a great acronym, and for the governor, it could really make him or break him politically."