Milwaukee's voucher program started 16 years ago as a nominal experiment involving 341 low-income students and seven schools. In many ways, the legislature viewed it as a sympathy measure toward a handful of struggling but respected community-based schools.

But the financial and ideological backers of vouchers had their sights on a bigger prize: a voucher program that would include religious schools and, over time, could rival the power of public schools. If dreams were to become reality, it would also usher in a universal voucher system to fund education.

That bigger prize is alarmingly close in Milwaukee. Given the program's recent expansion by the state's Republican-controlled legislature (abetted by a Democratic governor fearful of losing re-election next November), the voucher program could become the state's fourth largest school system.

Voucher proponents in Milwaukee have pushed for continued expansion. When the program began in 1990, voucher schools could only have 49 percent of their students receiving publicly funded vouchers. The theory was that the schools could still be considered "private," and that the private-paying students could help ensure quality. In addition, a cap was set and the number of voucher slots could not exceed 1.5 percent of the enrollment of the Milwaukee Public Schools (MPS). By 1995, schools were allowed to be 100 percent dependent on voucher students and public dollars (yet still call themselves "private" schools).

The most important expansion was in 1998, when religious schools were allowed to participate and voucher enrollment was allowed to grow to 15 percent of the MPS enrollment, or about 15,000 students.