Schaffhausen is the latest Swiss canton to introduce rules about the funding of political parties and interest groups involved in campaigns ahead of votes and elections.
53.8% of voters came out in favour of the initiative by the youth chapter of the left-wing Social Democratic Party, according to officials.
There are currently no regulations at a national level about the financing of political parties, regularly drawing criticism by the anti-corruption panel of the Council of Europe.
So far, five cantons, notably in French- and Italian-speaking Switzerland, have set similar regulations.
A people’s initiative launched by the Social Democrats, which won enough signatures for a nationwide vote, is currently discussed by parliament before voters have the final say at a later stage.
The nationwide proposal calls for a ban on anonymous financial support of parties and other political groups. Parties would have to declare the origins of any donations of more than CHF10,000 ($10,295). Citizens and committees funding political campaigns with more than CHF100,000 would also have to be transparent about their donations.