The Clinton machine was preparing for her run before the last election was over. The only question is will she run in 2004 or 2008.
She prefers 2004 because she wants to have a Bush - Clinton - Clinton - Bush - Clinton - Clinton legacy of succession. There is no way Gore will get the nomination again. Edwards wants to be Hillary's VP. Daschle and Kerry are throwaways incase Hillary doesn't run in 2004. They can run and still hold their Senate seats, pocketing millions in unspent campaign money and pushing their agenda.
Hillary can have the nomination any time she wants it. She is just waiting to see which year is best for her.
Daschle is up for reelection in '04. I don't think SD law allows simultaneously running for two offices (unlike CT and TX) but I could be wrong about that.