A proposal to allow citizens a final say by secret ballot on who should be granted Swiss passports was heading for defeat Sunday, dpa reported.
Results so far showed the move backed by the right-wing People's Party, UDC/SVP, had failed to gain enough support from the people.
Two other issues looked as though they would be rejected too: to make the health insurance system more transparent and to limit the information given by the federal authorities on ballot issues.
The UDC/SVP had launched the initiative to return to the ballot box to decide naturalization application after it was outlawed five years ago by the Federal Court.
The party said the people should decide not the judiciary. They also challenged the court over the right of appeal by rejected candidates.
The government has urged voters to reject the proposal preferring the decision to be made by elected bodies with a right of appeal.
The court made its ruling after a number of controversial decisions which saw a vast majority of citizens of Balkan origin refused Swiss nationality in the commune of Emmen near Lucerne.
In contrast to the national trend, voters in Emmen voted 51 per cent in favour of the UDC/SVP reform on naturalization.