1.For a candidate in a marginal seat, securing that vote is important.
对于一个在拥有微弱优势席位的候选人，确保这样的选票是很重要的。
2.Mps representing marginal seat are worried about the government's poor show in the opinion poll.
代表边际席位的下院议员对政府在民意测验中的坏的表现表示忧虑。
3.He won the most marginal seat by only two votes.
他只以两票的微弱优势当选。