The proposal - known as education savings accounts - is the latest evolution of the ongoing national push to expand vouchers in states. In Tennessee, Lee is backing policy that would allow families to use up to $7,300 in state funds to spend on private school tuition and other approved expenses. Families in qualifying schools districts would have to meet certain income levels to receive the voucher funds.
"I'm very encouraged today. I certainly believe that today was a historic day given that the House and Senate have never before both passed an education savings account bill. Mostly for me, it's an important day for the children of Tennessee," Lee told reporters after the Senate vote.
However, the Senate's version, which passed 20-13, conflicts with what House members narrowly passed earlier this week by just one vote. That means the two chambers will form a joint "conference committee" to seek a solution.
For one, Senate lawmakers want the program to apply only to the metro Nashville and Shelby County - which includes Memphis - and would require the Department of Education to verify the income of parents participating in the program.
Meanwhile, in the House, that version includes having parents to verify their immigration status - a requirement that has raised legal concerns and objections from Senate members - and would currently apply to the state's top four most populated counties.
Lee repeatedly declined questions on whether he preferred the House or Senate version of the bill.
"This process is one in which things change and you come to an ultimate decision by all parties involved," he said. "And we'll see where that lands."
Lee acknowledged he had been calling and urging lawmakers to vote in favor of the bill. In particular, newly elected Republican state Sen. Bill Powers cast his first vote Thursday in favor of the voucher bill after promising during a campaign he was opposed to school vouchers.
Powers was elected Tuesday in a special election and sworn in Thursday.
Lee said he appealed to Powers but denied that he offered Powers or any state elected officials incentives for their support.
Tennessee's voucher plan has caught the eye of both President Donald Trump and Education Secretary Betsy DeVos, who have both tweeted their support of the proposal. Yet despite the outside national attention, it's been an uphill battle to secure enough support inside the GOP-controlled Statehouse all session.
The proposal has undergone multiple amendments and last-minute changes in hopes of wooing skeptical lawmakers. The effort took a particularly dramatic turn on Tuesday when the bill appeared to have failed on the House floor, but was narrowly saved after a Knoxville lawmaker was persuaded to switch his vote in exchange for having his county removed from the program.
That's because some fear that participating local public schools would receive fewer public dollars in the voucher program.
Tennessee lawmakers have long attempted to expand vouchers, but until this year have faced repeated opposition from lawmakers concerned about taking limited resources from the state's public schools.
The political landscape has shifted after key changes in House leadership, and the election of a slew of new lawmakers including Lee, a first-time politician who campaigned for governor on school choice. The education savings account bill has since become Tennessee's top legislative battleground, with Lee supporters calling the proposal the administration's most important bill of the session.
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