A key Senate committee today (Friday) killed Governor Carlson's latest school vouchers proposal. The Governor has promised to veto all other school spending until he gets a vouchers plan, and lawmakers are steeling themselves for a showdown at the end of the legislative session, next month. Minnesota Public Radio's Martin Kaste reports: The Senate K-12 Committee didn't surprise anybody when it voted down the Governor's vouchers plan; their counterparts in the House already killed the bill last week. The Governor wants a law to let students spend state dollars on private education, something he believes would reform the whole school system by making it more "customer-oriented." The Governor has been fighting the Legislatu