The rightwing Swiss People's Party and the Greens look set to make the biggest gains in Sunday's parliamentary elections, a nationwide exit poll indicates.
The centre-left Social Democrats will most likely be the big losers for the first time in 20 years, according to the survey commissioned by swissinfo's parent company, the Swiss Broadcasting Corporation.
A second exit poll is due shortly, but final results as well as a breakdown of the seats for the House of Representatives are not expected before Monday morning.
The People's Party – one of four governing parties - took 28.8 per cent of the vote in the elections for the House, up 2.1 per cent on 2003, according to the gfs.berne polling institute.
The Social Democrats appear to have suffered the biggest losses, taking 19.1 per cent, down from 23.3 per cent four years ago.
The Radicals and the Christian Democrats, the two centre-right parties in government, won 15.9 per cent and 14.6 per cent respectively.
These four parties have held more than 75 per of the seats in parliament for decades.
The true winners of the 2007 elections could be the Greens. They are forecast to increase their share of the vote to 9.5 per cent from 7.7 per cent.
In elections to the 46-seat Senate, near-final results show little change after Sunday's ballot. Run-off elections will be held in at least seven of the country's 26 cantons.
The president of the People's Party, Ueli Maurer, said his party was committed to working for consensus in the cabinet in an apparent reversal of its confrontational style in the election campaign.
The Social Democratic Party admitted defeat, saying it had failed to convince voters with a programme of social and environmental issues.
Mud-slinging in the run-up to election day increased voter interest slightly, and turnout was estimated at an above-average 47.9 per cent.
The campaign was dominated by controversy over Justice Minister Christoph Blocher and his People's Party's hard-line stance on immigrants and crime.
A People's Party poster campaign depicting white sheep kicking a black sheep off a Swiss flag drew worldwide media attention and criticism from the United Nations.
Other issues, such as climate change, taxes, social security and unemployment were pushed into the background.
The increasingly aggressive campaign escalated into violence at a rally in the capital, Bern, two weeks ago.
Police clashed with leftwing militants who tried to interrupt a public gathering of the People's Party and their supporters.
For the first time in nearly 50 years the parliamentary elections focused on the personalities of cabinet ministers.
Traditionally they act neither as party leaders nor are they directly accountable to their political parties.
This is widely believed to have been the most expensive election campaign in Swiss history with parties spending at least SFr50 million ($42 million).
No detailed figures are available, and Switzerland does not have a transparency law on the financing of political parties.
More than 3,100 candidates, including 44 Swiss expatriates, ran for seats in parliament for the next four-year term.
The two chambers will choose the new cabinet at a joint meeting in December.
Voters choose the 200 members of the House of Representatives and most members of the 46 Senate for the next four-year term.
The four main parties – People's Party, Social Democrats, Radicals and Christian Democrats – control more than 75% of the seats in parliament and share the seven cabinet posts.
An alliance of Greens and other leftwing parties are the biggest opposition grouping with 14 seats.
Both houses of parliament will meet on December 12 to elect the new cabinet.
Percentage and seats in both houses of parliament - 2003 elections:
People's Party: 26.7% and 63 seats
Social Democrats: 23.3% and 61 seats
Radical Party: 17.3% and 50 seats
Christian Democrats: 14.4% and 43 seats
Greens: 7.4% and 13 seats
Others: 10.9% and 16 seats
Total: 100% and 246 seats
Swiss Abroad Candidates
A total of 44 Swiss expatriates are standing for a seat in the House of Representatives - three times more than in 2003.
According to the Organisation of the Swiss Abroad (OSA), between 30% and 50% of Swiss living abroad who are registered to vote were expected to exercise their right.
Over 110,000 Swiss abroad were registered to vote.