A proposal by a coalition of pacifists and centre-left parties to ban the export of weapons appears to be losing support ahead of a nationwide vote on November 29.
A survey by a leading research and polling institute found 50 per cent of respondents rejecting the initiative, while 39 per cent came out in favour. Eleven per cent are still undecided.
Opponents increased their share by seven per cent over the past month, while supporters dropped slightly.
The government and three of the four main political parties have come out against an export ban, saying it would lead to important job losses in the industry.
The centre-left Social Democrats and the Greens argue the sale of weapons contradicts Switzerland's traditional neutrality.
"Rejection of the initiative at the ballot box is likely. Most citizens appear to be convinced that there are tough rules are in place to avoid abuses," said Claude Longchamp of the gfs berne institute which conducted the survey, on Wednesday.
The poll among 1,213 citizens across the country a week ago was commissioned by the Swiss Broadcasting Corporation, swissinfo's parent company.
In 1997 a similar initiative to ban arms exports was rejected by three out of four voters.
Urs Geiser, swissinfo.ch