By Imogen Foulkes
BBC News, Bern
Swiss voters go to the polls on Sunday after a general election campaign marred by riots and accusations of racism.
Riot police were deployed when violence flared at a Bern poll rally
The right-wing Swiss People's Party (SVP), already the largest party in the parliament, is leading in the opinion polls and now expects at least 27% of the vote.
But the party's campaign has focused almost entirely on immigrants.
Its controversial poster, showing three white sheep kicking a black sheep out of Switzerland, brought sharp criticism from the UN's special rapporteur on racism, Doudou Diene.
An even more graphic SVP video contrasts the "heaven" of a Switzerland in which trains run on time and families hike in the Alps, with the "hell" of veiled Muslim women, immigrant teenagers attacking Swiss girls and black men standing idly in the street.
The SVP's charismatic leader, Christoph Blocher, who is also justice minister, dismisses charges that the campaign has been racist, explaining that the party simply wants to gain support for its policy to deport foreigners who commit crimes.
The controversial poster bears the slogan "For more security"
"The People's Party has said clearly we have to set rules for foreigners and immigrants," Mr Blocher told journalists at a campaign rally.
"We've got to be strict with them. We've got a rising crime rate - people from the Balkans especially are committing crimes - we think they and their families should be deported."
But of Switzerland's population of just 7.5 million, 1.5 million are immigrants, or the children of immigrants, and they are growing nervous of the SVP's rhetoric.
Glenda Loebbell Ryan, a black woman originally from South Africa, has been a Swiss citizen for years. She is concerned by the black sheep posters.
"I got off the train in Bern and those posters were everywhere," she said.
"And all of a sudden I had a sense I was back in South Africa, during the apartheid years, and I was in the middle of all the white racist apartheid rulers," she said.
"It made me feel very uneasy, and it was the first time I had that feeling in Switzerland."
Andrew Katumba, son of a Ugandan father and a Ukrainian mother, is also a Swiss citizen and now running for parliament. He sees the SVP's vision of Switzerland as clichéd and outdated.
"Switzerland is a multicultural country. It's a reality," he insists.
"It's not about Heidi and cows and chocolate anymore. This country has changed immensely - there are new Swiss, immigrants, and they want to participate and to vote and to realise their vision of Switzerland."
A big factor in this election campaign has been the fact that none of the other major parties has challenged the SVP's campaign style.
Blocher has a reputation as a fiery orator
The Liberals and Christian Democrats are offering bland posters with head-and-shoulder shots of their candidates. Their main policies are complicated proposals on tax reform.
The Social Democrats, currently second in the opinion polls with around 22%, have run a low-profile campaign focussing primarily on the environment.
So when the SVP decided to hold a march and rally in Bern's historic old town earlier this month, it was Switzerland's dedicated extreme left-wing groups, seen more often at anti-globalisation demonstrations, that decided to oppose them.
The ensuing riots, with scenes of tear gas and burning cars, made headlines around the world and spread shock among the Swiss, who are used to a much calmer, more consensus-based political style.
"I think many Swiss will be happy when this election is over," says Georg Lutz, a political analyst at the University of Bern.
"There's been a lot of provocation, especially from the People's Party, and I think that although that may win votes, it will also lose votes."
'We need each other'
A visit to Bern's weekly farmers' market does indeed reveal some concern at the tone of this election campaign.
Left-wing groups tried to disrupt an SVP rally in Bern in October
"It's all so silly I can hardly bear to comment on it," says one young father, as he straps his son into his pushchair. "They are making a lot of noise about nothing, it's too stupid."
"I don't like that sheep poster," says a young woman. "It's a shame for Switzerland, we're not really like that."
"And we're making ourselves look ridiculous to the rest of the world," adds her friend.
Older shoppers, however, have some different views.
"I think if you commit a crime you should leave," says one farmer, busy selling her produce.
"About 20% of our population is foreign now and some of them are very aggressive. I think portraying them as sheep is too nice - I like sheep," she says.
A flower seller shakes her head at these words.
"Personally I am for living together, with people," she says.
"We need to stop thinking that Switzerland is something very special and we have to keep the foreigners out, because we need each other, very much."
For Mr Lutz of the University of Berne, that is the important fact behind all the rhetoric about immigration to Switzerland.
"One thing we all agree on is that Switzerland needs foreigners," he explains.
Right-wing parties fear Swiss traditions are under attack
"If we were to throw all the foreigners out our economy would collapse from one day to the next. Everyone knows that, even the People's Party knows that."
Despite its lead in the opinion polls, the SVP cannot hope for an overall majority in parliament.
Switzerland's complicated system of proportional representation means the election is likely to deliver a coalition government once again.
Mr Lutz believes that once the sound and fury of the election is over, the big task will be to promote better integration and acceptance of Switzerland's immigrants.
One solution, he suggests, would be to offer them the vote.
"At some stage, we will have to consider whether giving foreigners the vote will help to integrate them better," he says.
"I do think that is by far the biggest challenge ahead of Switzerland, rather than trying to keep as many foreigners away as possible," Mr Lutz says.