By Marina Depetris and Cecile Mantovani
BERN, Oct 20 (Reuters) - The Greens made strong gains in Switzerland's election on Sunday while the far-right party lost ground, early results showed, potentially putting environmentalists in the mix for a seat in the coalition that has governed the country for decades.
The Greens rode on voters' concerns about climate change in the parliamentary election and could dilute centre-right parties' grip on power.
Changing just one member of the seven-seat cabinet would be a political sensation. The Greens have never had a seat in the four-party Federal Council.
The far-right People's Party (SVP), which won record seats in 2015 amid Europe's refugee crisis, slipped 3.1 points to 26.3% while the Green Party's share surged 5.6 points to 12.7% of the vote, according to a projection for broadcaster SRF based on partial results.
The smaller, more centrist Green Liberal Party (GLP) also advanced to 7.6%, bringing the two parties' combined strength to more than 20% should they overcome policy differences and decide to join forces.
Switzerland's system of direct democracy gives voters a final say on major issues decided by referenda, but Sunday's results showed the green wave gripping Europe has reached Switzerland.
The centre-left Social Democrats remained second on 16.5% and the centre-right Liberals (FDP) third at 15.2%, but the Greens leapfrogged the centrist Christian Democrats (CVP), which has one seat on the Federal Council.
Cabinet seats have been divvied up among the SVP, SP, FDP and CVP in nearly the same way since 1959. The three biggest parties get two seats and the fourth-biggest gets one under the informal "magic formula" system.
In December, the two parliamentary chambers will elect the government, but in the past it has taken more than one national election cycle for that selection procedure to change the cabinet lineup to more closely reflect the results.
"Climate change: I think it is pretty obvious that is the most important topic of all in our time and age. There is really not any time to lose," said one 25-year-old psychology student, who gave her name only as Anja, at a Bern polling station.
Analysts caution against expecting too radical a shift after a campaign that was light on typical hot-button issues such as migration and Swiss ties with the European Union that have given the anti-EU SVP a boost in the past.
(Writing by Michael Shields, Additional reporting by Emma Farge Editing by Christina Fincher/Dale Hudson/Susan Fenton)
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