By quoting "far-left" the poster is indicating that he himself does not believe that Obama is far left but that it is something someone has said or written abou

By quoting "far-left" the poster is indicating that he himself does not believe that Obama is far left but that it is something someone has said or written about Obama. https://en.wikipedia.org/wiki/Scare_quotes https://en.wikipedia.org/wiki/Scare_quotes