Clinton rejects the notion of a re-vote for Florida and says that she would "not accept a caucus" in Michigan (or Florida):

I would not accept a caucus. I think that would be a great disservice to the 2 million people who turned out and voted. I think that they want their votes counted. And you know a lot of people would be disenfranchised because of the timing and whatever the particular rules were. This is really going to be a serious challenge for the Democratic Party because the voters in Michigan and Florida are the ones being hurt, and certainly with respect to Florida the Democrats were dragged into doing what they did by a Republican governor and a Republican Legislature. They didn't have any choice whatsoever. And I don't think that there should be any do-over or any kind of a second run in Florida. I think Florida should be seated.

Clinton won Florida handily, so she already has an advantage there. Plus, both she and Obama were on the ballot there, so she's got some cover. Only her name was on the ballot in Michigan, though, last time, so she'll have a harder time opposing some kind of re-vote for the state. A Michigan caucus would probably play to Obama's strengths, however, so she she'd like to avoid that.