Here's an explanation of the rules for tonight's Vice-Presidential debate between Joe Biden and Sara Palin.
The rules will be a lot like the Presidential debate we saw last week: One of the candidates will be asked a question and be given 90 seconds to respond -- 30 seconds less than the two minutes from the Presidential debate -- followed by a 90-second rebuttal for the other candidate, and then a free-flowing discussion on this between the two candidates. But it won't be quite the same.
The big twist here is that the rules were modified -- at the insistence of the McCain campaign -- to limit those back-and-forth exchanges to a mere two minutes, and not the five-minute periods that we saw at the Presidential debate.
This was widely seen as an accommodation for Sarah Palin, allowing her to retreat to sound-bites that can fill the time up rather than having to spontaneously take on Joe Biden on the merits of this or that issue.