Geneva - Switzerland voted on Sunday on whether to make it easier for third generation immigrants to become citizens after a campaign tainted by anti-Muslim messages and charges of religious prejudice.Preliminary results pointed to the measure being approved, in what would be a defeat for the far right nationalist Swiss People's Party (SVP), which put issues of Islam and national identity at the centre of the debate.The government as well as most lawmakers and political parties supported the proposal that would allow the grandchildren of immigrants to skip several steps in the lengthy process of securing a Swiss passport.Becoming citizensAccording to a migration department study, less than 25 000 people in the country of about eight million currently qualify as third generation immigrants, meaning they have at least one grandparent who was born here or acquired Swiss residency.Nearly 60% of that group are Italians, followed by those with origins in the Balkans and Turkish nationals.Debate on the proposal had nothing to do with religion at the outset, said Sophie Guignard of the Institute of Political Science at the University of Bern. It was the SVP, a party repeatedly accused of demonising Islam, that focused on the risks of more Muslims becoming citizens and the possible "loss of Swiss values", said Guignard.Polls closed at midday and most in the wealthy Alpine nation had already voted by mail. The gfs.bern polling institute reported that the early trend indicated a win for the "Yes" camp. Local lawsEight cantons, including major population centres like Geneva, Zurich and Basel, voted to approve the measure with two small cantons voting "No", final results showed. A change to citizenship laws requires a constitutional amendment, meaning the Yes side needs to win both a majority of votes and a majority of Switzerland's 26 cantons. Sunday's referendum is one of four each year for voting on subjects affecting federal as well as local laws and institutions.