European leaders interpreted the result for a sign They hadn’t swung Swedish opinion supporting the Extensive endeavor to transform Europe into a cohesive and integrated drive.specifically the phrase “interpreted the result for a sign”is not intelligible to me .http://whatthezeus.com/money/in-a-referendum-sweden-resoundingly-reject-the-euro/?utm_source=outbrain&utm_medium=cpc&ad_title=Sweden+Surprises+EU+In+Referendum&origsrcname=World&utm_term=World&campaign=jsd000
Though not being used in a religious sense in any way, the phrase "for a sign" or "as a sign" as used here is derived from religious roots. "Our good harvest is a sign of heavenly favor" or "it is a sign from God." Please refer to the definition of sign (noun) #6b.
So, in your example, "sign" is used to mean an indicator or proof of a conclusion.
European leaders interpreted the result as proof/an indicator/evidence that they hadn't swung Swedish opinion....
Please note that @FumbleFingers is correct. "For a sign" is grammatically correct, but a very uncommon way to form the clause. Natives commonly use "as a sign."
"For a sign" means the results were literally a sign. Given the religious root of the phrase, it would connotate the results were literally a sign from heaven.
"As a sign" means "sign" is a metaphor for something else. This is why this phrase is more commonly used.
The author of the article may have meant the interpretation of the results was divinely inspired, but it's more likely the author made a simple lexical mistake.