I think it will happen soon, possibly as soon as 2012. If Obama does poorly in the next four years, I can easily see both Hillary Clinton and Sarah Palin running for president. It would be fascinating if both won their nominations.
I don't think Condoleeza Rice will ever run for president. I know politicians change their minds all the time, but I think she actually means it. She jokingly says that she'd rather be NFL Commissioner than president. I would definitely consider voting for her if she ran, Palin as well.
Liddy Dole will never be president. She ran in 2000 and had very little support. She's not a very dynamic speaker and has two big anchors around her neck. She is the wife of failed presidential candidate Bob Dole and she just lost her Senate seat in North Carolina.
Another possibility is Democratic Kansas Governor Kathleen Sebelius. She's one of the rising stars in the Democratic party and appeals to conservatives and moderates. I don't know a whole lot about her outside of that, but she warrants a serious consideration for president.
On the Republican side, there's Linda Lingle of Hawaii. She is very popular in a very Democratic state and has cross appeal like Sebelius does. While not mentioned normally in discussions for presidential contenders, I could easily see her getting significant support.
Another one is Republican Jodi Rell of very-Democratic Connecticut, who also has a very high popularity rating.
The only problem Lingle and Rell could have is that they come from very small states. Even though they're successful, like Sarah Palin, they would get knocked for having very small constituencies.
Notice that I've basically been mentioning governors. Governors usually have a much easier time becoming president since those are high executive jobs. Historically, senators have had a very difficult time. This time was an exception as both candidates were senators.
