Should mainstream parties have a blacklist of potential coalition partners?

One of the stories of 2014 was the success of populist and anti-establishment parties in the European Parliament elections in May. Looking ahead to the big elections of 2015 year, Duncan McDonnell writes that mainstream parties now face a dilemma over how they deal with radical parties in national parliaments.

ESO: Background information: Sweden parties reach budget deal to avoid snap election http://www.europeansources.info/record/sweden-parties-reach-budget-deal-to-avoid-snap-election/

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