What is going on with the Democratic party in the USA?

Every time there is a Presidential election, they rehash the same tired old guys that didn't win the last time.

Sanders missed out last time to Clinton who was by then stale herself.

Now Sanders comes back for another go, pushing 150 years old & loses out to someone who was vice president for 8 years & is himself 149 years old.

Believe it or not, I'm not ageist, because I wouldn't mind if these guys were fresh faces, but they're not; just the same old guys rehashed guys again.

Where is the young fresh face in the Democratic party; the new Barack Obama, so to speak?