PHOENIX (AP) - Gov. Doug Ducey has signed a major school voucher expansion bill that will extend eligibility to all the state's schoolchildren.

Ducey's signature came after the House voted Thursday evening to enact the measure with just one vote to spare. No Democrats voted for the bill and four Republicans also were opposed.

The Senate also passed the measure Thursday by just one vote. One Republican joined all Democrats in opposition.

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The bill Ducey signed caps total program enrollment at about 30,000 students in 2022. Changes to the original proposal also cut the cost of the program from $24 million to a $3.4 million savings.

Opponents say wealthy parents will now be able to use public money for private schools. Backers say it a smart school choice measure.