tax cuts for middle class?

I am sure this has been covered, but I have a couple of questions about the tax cut/extension debate. Why are the Dems worried about the Bush Tax cuts expiring, after all I can remember during the original debate that these tax cuts only benifited the rich. Now all I hear is that if these tax cuts arnt extented for the middle class, they will be hurt(which they will be). Which is it? Next Nancy Pelosi says that unemployment benifits are the best stimulus for the economy, (since the Bernacke just said that 10% unemployment may last for 5 years,...