The Missouri legislature moved one step closer on Monday to putting on the ballot a measure that would gut an anti-gerrymandering initiative passed by voters last year. The proposal, if it becomes law, would set the stage for the state to exclude non-citizens from its redistricting process, kicking off a major legal battle over who deserves political representation in the country.

The Missouri House passed the ballot measure out of its chamber Monday. The vote was f 104-49, with eight Republicans opposing.

It moves now to the state Senate, and if passed there, it will need final approval from voters in the 2020 election.

Supporters of the bill, known as HJR 48, have described it as a fix to the so-called “Clean Missouri” citizen ballot initiative approved by voters last year. Clean Missouri implemented an ethics overhaul while reforming the redistricting process in the state.

The new measure’s top-line proposal would change Clean Missouri’s $5 limit on lobbyists’ gifts to lawmakers to an outright ban on lobbyists’ gifts — a move that will likely appeal to ethics reform-minded voters.

However, buried in the proposal, through amendments added to the bill after its initial introduction, are measures that would largely dismantle Clean Missouri’s anti-gerrymandering provisions. Another amendment added to the bill last week changes its redistricting language to mandate that redistricting would be done on the basis of “one person, one vote” rather than total population.

That change has been interpreted as a move that would allow the state to try to draw to draw its districts on a citizen-based metric, which would shift political representation away from areas with relatively large immigrant populations.

Such a push would come as the Trump administration has sought to add a citizenship question to the census, which could provide Missouri and other states the data they’d need to implement such a redistricting overhaul. The Supreme Court, which heard a case challenging the question last week, appears inclined to let it stay on the decennial, despite widespread concern — including from the Census Bureau — that it will distort the accuracy of the count by discouraging participation on the survey.

Some conservative justices have hinted that they’d like to see a test case that would allow them to consider whether states and localities can exclude non-citizens when they draw their districts.

Critics of the Missouri legislation currently under consideration also pointed to the use of the word “citizen” in an amendment that tweaked a requirement in the Clean Missouri initiative related to protecting minorities from vote dilution.

Additionally, the “one person, one vote” amendment and the underlying legislation were sponsored by the same GOP lawmaker who last year pushed for legislation explicitly excluding non-citizens from being counted for redistricting.

The lawmaker, Rep. Dean Plocher (R) did not respond to a TPM request for an interview submitted to his office.

More broadly, Plocher’s bill would eliminate a provision of Clean Missouri requiring that a nonpartisan demographer would be appointed to draw the legislative maps. The new measure would, more or less, return the state to its previous system of a bipartisan redistricting commission with members recommended by each party in the legislature and appointed by the governor.

Meanwhile, the legislature is also considering legislation to make it harder to file citizen ballot initiatives like the original Clean Missouri.