SIOUX FALLS, S.D. — Supporters of a constitutional amendment targeting government corruption have turned in enough valid signatures to put the ballot question before South Dakota voters in 2018, the state’s chief elections official said Friday.

More than 51 percent of voters supported a similar initiative in November 2016, but Republican lawmakers scrubbed it from state law just months later, citing constitutional concerns. If passed, the new constitutional amendment would largely be protected from legislative changes.

Secretary of State Shantel Krebs’ office said in a statement that the amendment is the first question to be placed on the November 2018 ballot. Measure supporters say it would put the state’s voters back in charge.

The newly dubbed Constitutional Amendment W would tighten campaign finance and lobbying restrictions. It also would create an independent ethics commission and prevent the Legislature from altering or rejecting laws approved by voters without returning to the ballot.

The amendment would replace a voter-imposed ethics overhaul called Initiated Measure 22, the initiative that South Dakota lawmakers repealed this year.

The amendment’s approval for the ballot comes as some lawmakers have discussed changes that would make it tougher for residents to bypass the statehouse at all. South Dakota, in 1898, became the first state in the nation to adopt citizen initiatives.

A proposal from the South Dakota House speaker would ban out-of-state fundraising for initiatives. Another legislative plan would make it harder for constitutional changes to pass at the ballot box. Both would require voter support to take effect.

“The political establishment’s ongoing effort to undermine and disrespect South Dakota voters is outrageous,” Doug Kronaizl, spokesman for pro-amendment group Represent South Dakota, said in a statement. “What began as anger and frustration over the Legislature’s brazen repeal of IM-22 has become a rallying point for South Dakotans of all political stripes who demand a cleaner government that respects its voters.”

The new amendment would create a seven-member state government accountability board with broad powers to serve as a citizen ethics commission. It would require lawmakers to put $389,000 annually indexed to inflation into a fund administered by the board.

The panel would investigate allegations of corruption and violations of lobbying, campaign finance and government ethics regulations. It would also have the authority to conduct audits of disclosures including for lobbying and campaign finance and impose sanctions such as fines on public officials.

The new amendment would also lower campaign donation limits. For example, it would decrease the contribution limit for a state representative from $1,000 a year from individuals to $500 per election cycle. Donations from corporations and labor unions to candidates or political parties would be banned.

Gifts from lobbyists to many public officials also would be barred. Currently, there’s an annual $100 limit on gifts that legislators and other public officials can accept from lobbyists, but gifts don’t include food, beverage or entertainment for immediate consumption, among other things.

The proposed amendment also prevents the Legislature from changing the ballot question process without a public vote.

The measure’s approval for the ballot could be challenged. The deadline for such a challenge is Jan. 29.

Backers needed nearly 28,000 valid signatures for the amendment to go before voters. Krebs says they turned in about 50,000 signatures, and a random sampling found roughly 71 percent were valid.