http://blog.livedoor.jp/yamajun1985/archives/49759517.html

As worrying as Britain First's popularity online may seem,
despite questions over the legitimacy of its Facebook following,
Arnoult ultimately has an optimistic outlook: "They aren't a legitimate party by any degree
so I'm not particularly worried about them ever having serious sway."

解説に納得しつつも自分学習してきた分詞構文の例だと
Arnoultが主語になるんでは？と思って混乱してブックマークに封印した・・