Last week the Joint Finance Committee of the Wisconsin legislature voted on a controversial school voucher expansion in the middle of the night, to the dismay of teachers, parents, and local school boards throughout the state.

Several moderate Republicans had pledged to resist an expansion of school vouchers beyond Milwaukee and Racine, especially in light of the recent, massive budget cuts to the state's public schools.

Instead, the Republicans reached a "compromise" among themselves, agreeing to expand the voucher program not just to nine new school districts, as Walker had proposed, but to the entire state -- in exchange for a small per-pupil increase in public school spending, worth about one-quarter of the per pupil cut in Walker's last budget.

Immediately after the statewide voucher expansion made the news, the biggest behind-the-scenes supporter of school privatization in Wisconsin and across the country made a public statement, announcing that the deal did not go far enough.

"It is disappointing that more children will not be able to attend the school of their parents' choice in the new statewide program," Betsy DeVos, chair of the American Federation for Children said in a statement. "Wisconsin families and children deserve quality educational options, especially those families with special needs children who saw their opportunities vanish when the committee voted to eliminate Gov. Walker's proposed special needs scholarship program."

The problem with the voucher expansion from DeVos's point of view is an enrollment cap that would slow voucher growth to 500 students in the first year and 1,000 students the year after that.

Public school supporters worry that the caps will be a temporary speed bump and that, as Senator Dale Schultz, Republican of Richland Center, told the Associated Press, "We are only one budget away from opening the floodgates. It's grown every single budget. By going statewide you sort of legitimize the concept."

But even the temporary cap may not last past Walker's budget signing in a couple of weeks.

DeVos's public statement could be read as a signal to the governor to use his line-item veto to remove the enrollment caps.

And there is reason to believe Walker is listening.

DeVos and her husband, Richard DeVos, personally gave more than $250,000 to Scott Walker's campaign during the recall election against him. And the American Federation for Children reported to its members that it spent $2.39 million in Wisconsin in 2012 to keep Republican pro-school-voucher candidates in control of state government. In the report to its membership, AFC touted its success putting money into state elections to support "school choice." Wisconsin was the state where the group spent the most in the last election cycle -- about one-third of all its political spending.

The Associated Press story on the voucher expansion quotes Assembly Speaker Robin Vos dismissing critics on both sides of the voucher debate. "Our goal is to have no changes made to the budget," Vos told A.P. reporter Scott Bauer.

But the budget could survive intact all the way to the governor's desk, and Walker could use his line item veto to lift the cap. (Wisconsin law allows the governor extraordinary leeway to cross out words in bills and thereby alter the meaning of the legislation. It is sometimes called "The Vanna White Veto.")

Why not? Already, the voucher deal has emerged over the loud objections of local school boards, teachers, parents, and even moderate Republicans in rural districts that are particularly threatened by the potential drain on school resources.

Republican Senators Mike Ellis and Luther Olsen originally pledged not to go along with a voucher expansion if local school districts were not allowed to decide for themselves whether to accept vouchers.

The Republican leadership overcame those objections with a little arm-twisting.

Clearly, public opinion is no obstacle.

There is no popular demand for vouchers. While the Joint Finance hearing room last week was packed with teachers with "no vouchers" t-shirts and signs who came to hear the discussion and stayed late into the night, there were no pro-voucher signs.

But there is a lot of PAC money behind the voucher drive.

The biggest out-of-state donors to Scott Walker and the Republicans during the recent round of recall elections in Wisconsin were pro-voucher individuals and groups.

The Wisconsin Democracy Campaign calculates that wealthy campaign donors and shadowy pro-voucher groups spent $10 million in Wisconsin in the last 10 years.

Among them:

Walmart billionaires Jim and Lynne Walton of Bentonville, Arkansas: The Walton family, the richest family in America, has spent hundreds of millions of dollars through their family foundation to promote school vouchers, charters, and other alternatives to public education. The Walton Family Foundation states on its website that it seeks to "infuse competitive pressure into America's K-12 education system by increasing the quantity and quality of school choices available to parents, especially in low-income communities."

Foster Friess: Friess gave Gov. Scott Walker $100,000 the day after the recall campaign was launched against him. Friess is the wealthy supporter of socially conservative causes -- and Republican presidential candidate Rick Santorum -- who infamously stated on MSNBC earlier this month that an aspirin could double as birth control for a woman: "You know, back in my days, they'd use Bayer aspirin for contraceptives," he said. "The gals put it between their knees, and it wasn't that costly." Friess has praised Walker and his fellow conservative governor Bobby Jindal for taking on the teachers' unions and "their education monopoly" in the service of "freedom."

Rex Sinquefield of Westphalia, Missouri: Through his Show Me Institute, Sinquefield has led a well-funded efforts to privatize public education in Missouri -- personally and through the 100 political action committees he created.

Bruce Kovner of New York: The conservative hedge fund billionaire who bankrolled major expansions of the Lincoln Center in New York City, and backs school privatization in New York.

Roger Hertog of New York: Another hedge fund billionaire in New York who supports school privatization. According to historian Allen Ruff, "Hertog is, among other things, a chairman emeritus of the Manhattan Institute, the influential conservative social policy think tank; a board member of the right-wing American Enterprise Institute and the Club for Growth, the arch-conservative political action committee.... Hertog introduced Wisconsin's Governor Scott Walker at a Manhattan Institute conference on 'A New Social Contract: Reforming the Terms of Public Employment in America.' Embracing the controversial Republican state exec, Hertog praised him as a figure who, in the tradition of James Madison, Louis Brandeis, Ronald Reagan and Rudy Guiliani, would someday be looked upon as one who had 'helped save the country.'"

But no group matches the money and clout of Betsy DeVos and the American Federation for Children.

Which is why her statement should make all Wisconsinites nervous.

If you liked this article by Ruth Conniff, the political editor of The Progressive, check out her story "Scott Walker's Sneaky School Voucher Plan."

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