GOP legislators join unions to oppose reform in Wisconsin.

School vouchers are usually opposed by teachers unions and their Democratic allies, but a dirty little secret is that some suburban Republicans oppose them too. The latter is the case in Wisconsin, where GOP Governor Scott Walker’s plan to get more kids out of failing schools is facing opposition from short-sighted members of his own party.

The Badger State’s 22-year-old voucher program currently covers Milwaukee and Racine. But in his budget for fiscal 2014-15, Mr. Walker wants to expand it to nine of the state’s worst school districts and increase funding by 9%. Under the proposed formula, students in districts that have at least two schools that get a D or F on their 2011-2012 performance report cards could use a voucher at a private school.

The plan would cover 500 new students in the first year, 1,000 in the second, and thereafter as many as qualified under the formula, which extends the voucher to students in failing schools whose families make 300% of the poverty level. The new areas include Beloit, Green Bay, Kenosha, Waukesha and Fond du Lac, and more than 40,000 children who currently attend lousy public schools would be eligible.

That should please Neenah Republican and Wisconsin Senate President Mike Ellis, who last year called Green Bay’s Preble High School a “sewer.” But Mr. Ellis has instead promised to block Mr. Walker’s proposal, saying that the Governor had not respected the input of eight or 10 Republicans who didn’t want more vouchers in the budget. “This is phase one of a wide-open school voucher program for the state,” Mr. Ellis moans.

But what would be wrong with that? According to the School Choice Demonstration Project, 94% of students who have received vouchers in Milwaukee graduate from high school, compared to 75% from the Milwaukee public schools. They’re also more likely to go to college.

Read the entire editorial here.

A version of this article appeared March 29, 2013, on page A14 in the U.S. edition of The Wall Street Journal, with the headline: Republicans Against Vouchers.