pledged delegate

基本解释

In the delegate count estimated by CNN he leads by around 120 if you count only pledged delegates and over 40 if you include “superdelegates” (bigwigs with ex officio vote at the convention).
根据CNN预测的情况来看，奥巴马承诺代表中的领先优势在120席左右，如果包括依职权在大选中投票的“超级代表”则优势减少到40席。

But I will say that it was really cool to be able to go into the voting booth on April 24, 2012 and see my name on the screen as a pledged delegate in support of President Obama.
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Clinton will argue the opposite case, of course, and will say, look, superdelegates have been given the power to follow their own conscience, and here is the reason they should follow their conscience and not follow the pledged delegate lead that Obama has.
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(in the US)a delegate at a national party convention who is mandated to vote for a particular candidate