大概解释一下：
竞选中领先在前的罗姆尼有望成为其他辩家（攻击）的目标,在大多数投票中,其他对手都以成双位的票数追赶着他,力图将其拖回到与大家更为接近的位置上来.
1.was expected to be 有望成为
2.a target of.的目标
3.bring him back closer to the pack 将其拖回到与大家更为接近的位置上来；
the pack用法很好,含义：a large number of people who are grouped together during a race or competition — usually singular ▪ In the last few seconds,she broke/drew/pulled away from the pack and won the race.▪ The company is trying to stay ahead of the pack.[=ahead of their competitors]
4.double digits 双位数
仅供参考,望高手指教,