though polls have shown a mix of results, it is more often than not mr. romney who is on the upward trajectory, if not always overtaking mr. obama, then, at least, cutting into his leads among important constituencies.
单词提示：poll n. 民意调查（结果）︳a mix of results 结果不一 ︳more often than not 通常；多半︳on the upward trajectory 处于上升的轨道→呈现上升趋势? ︳overtake vt. 赶上；超过 ︳cut sb's leads among constituencies. 在几个选民区中削弱某人的 优势
今天要讲的是词组 more often than not，这个词组可以排得上私信问题中的top10。这个词组词典是有收录的，比如剑桥词典：
cambridge advanced learner's dictionary
cambridge advanced learner's dictionary
从词典对它释义可以看出，它的基本词义是：往往，多半；通常。
这个词组的逻辑理解是是：it's x more often than it's not x；it actually happens more than it doesn't happen.
比如：it rains here more often than not = it rains here more often than it doesn't rain here
柯林斯词典更是给出了它的频率范围：in more than half the instances 频次是超过50%的，但并非是一直发生，也不是一定发生。
所以，more often than not 可以理解为：quite often but not all the time.
所以，原文的外文句子大家能够翻译吗？
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