MADISON, Wis. — The Republican-backed effort to eliminate the Wisconsin state treasurer position is moving closer to approval in the Legislature, despite opposition from those who say powers of the office should be restored after years of being whittled away.

A state Senate committee voted 3-1 on Tuesday to approve the constitutional amendment, sending it to the full Senate for consideration as soon as next week. It is up for a vote in the Assembly on March 9.

If by legislative chambers pass it, as expected, voters statewide would have to approve it in the April 2018 election before the constitution would be amended to eliminate the office at the end of that year.

Republicans have already successfully done away with most of the treasurer's duties since 2011, concluding with transferring the unclaimed property division to the Department of Revenue in 2014.

Opponents of eliminating the office, including former three-term Treasurer Jack Voight, argue that its power should be increased rather than continue to have its duties transferred under control of the governor.

"In my opinion it's a real power grab," said Voight, a Republican. He said the three treasurers who succeeded him were "flunkies" who "didn't give a damn" about the office. Two of them, including current Treasurer Matt Adamczyk, advocated for eliminating the office.

Adamczyk's predecessor, Kurt Schuller, ran in 2010 wanting to do away with the office but later changed his mind and fought removal of the unclaimed property duties.

"This is a very grave mistake," Democratic Sen. Kathleen Vinehout, of Alma, said before casting the only committee vote against the measure. "We have not thought this through. ... What we need are checks and balances."

The measure's sponsor, Republican state Rep. Michael Schraa, said the treasurer position is merely symbolic and "a relic of the past." And co-sponsor state Sen. Dan Feyen, a Republican from Fond du Lac, said the treasurer's office "has no purpose and no reason to exist."

Putting the question of whether to keep the office on the ballot will give the people a chance to decide whether they want it, said Democratic Sen. Fred Risser, of Madison. But he conceded most people have no idea who the treasurer is or what their responsibilities are.

The treasurer's only remaining responsibility is to sit as a member of the Board of Commissioners of Public Lands, a little-known entity that manages trust funds built through fees, fines and land sales.

The board is comprised of the treasurer, attorney general and secretary of state. Part of the money it distributes from the Common School Fund goes to Wisconsin's public school libraries. The money is the only dedicated source of state funding for public school libraries. For many school districts, it is the only money available to them to buy library books, newspapers, periodicals and other resources.

Last year, public school libraries received $32.1 million from the fund.

The Wisconsin Educational Media and Technology Association, which advocates for public school libraries, also opposes the proposal.

The group, in a letter it submitted to lawmakers, argued that the current board members are "ideal custodians" of the fund because they don't play a leading role in K-12 school funding or the state budget process.

It worries that replacing the treasurer with the lieutenant governor on the board could have unintended consequences jeopardizing the future performance of the fund.

The treasurer's salary is $69,936 a year.