Swiss voters have narrowly backed a referendum that would restrict immigration (50.34% of the vote was "yes", the balance was "no"). A map showing how different parts of Switzerland votes is here.
Notably, "the Yes vote was higher in cantons with fewer immigrants." This is also true of political support for anti-immigration measures in most of the United States and in other developed countries where immigration is a political issue.
Tyler Cohen discusses the results at Marginal Revolution in an analysis that is mostly wrong. He suggests that there is some absolute threshold of foreign born percentage that triggers backlash. But, as the fact that these kinds of measures are supported mostly strongly in places with relatively low immigrant percentages indicates, this theory almost surely misapprehends the social and political dynamics driving xenophobia.