(Bloomberg) -- Chilean voters are likely to reject the draft of a new constitution, according to two of the final polls published before next month’s referendum.

About 45.8% of respondents plan to vote against the proposed charter on Sept. 4, up from 44.3% the week prior, according to a Pulso Ciudadano opinion survey released late on Friday. Another 32.9% said they will back the constitution, down from 33.9% before, while 15.7% are undecided.

Pollster Cadem also published fresh data later on Friday showing 46% of people would reject the charter --unchanged from last week’s measure-- in contrast with 37% who would approve it, down from 38%. Undecided went up to 17%, from 16%.

The figures come ahead of an Aug. 20 limit on the publication of polls regarding the referendum.

The new constitution was written in response to protests in 2019-2020 against inequality and poor public services. Yet it has failed to garner the support many expected, prompting government allies to propose a series of changes to its more controversial points in an attempt to swing next month’s vote. While the document’s backers say it would strengthen social rights and protect the environment, detractors warn it will deter investments and damp growth.

Investors are closely watching the polls in the lead-up to the vote. Chilean politics, including any news on the plebiscite, will be the main driver behind domestic bond moves this month, according to a Bloomberg News survey of traders and analysts.

There are mounting signs that uncertainty over Chile’s magna carta could linger well beyond the referendum, with President Gabriel Boric vowing to pursue another constitutional rewrite if the current proposal is shot down. 

Meanwhile, congress recently approved a bill lowering the legislative majorities needed to amend the current charter. Lawmakers are also pushing a proposal to give the president more leeway to lay the groundwork for a new constitution.

Boric’s administration, which has reiterated that both the options of approving and rejecting the charter are legitimate, is facing a probe from a government watchdog over allegations it used public funds to urge people to vote in favor.

The Pulso Ciudadano poll surveyed 2,089 people on Aug. 16-19. It has a margin of error of plus or minus 2.1 percentage points. Cadem considered 1,007 cases, surveyed on Aug. 17-19, and carries a margin of error of plus or minus 3.1 percentage points.

(Updates with Cadem data on third and last paragraphs)

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