and of course he shouldn't.

It is possible but not probable. Her lead is larger than the lead Obama ever held during the 08 elections, and she just couldn't catch up. The same scenario will likely play out this time, with Bernie in Hillary's 08 position.

because if I remember right she won some big states late in the game like PA. and CA.
but was Obama's lead smaller because she had a lot of super delegates?

between 08 and 16 elections to that point. Clinton is just doing better this time around and has larger numbers than Obama did in 08. I'm not sure how long everyone else was in 08 election, Edwards and whoever else was in then, pulled some of the numbers that are being split just between Bernie and Hillary now.

http://www.dailykos.com/story/2016/3/5/1496804/-Comparing-Delegate-count-between-2016-and-2008

Obama had done a lot of super delegate work in 08, was ahead in primary and caucus delegates, and that added with the problems with Michigan and Florida jumping ahead, gave him the win. Hillary is estimated to have had more votes total, but it was the delegate numbers that decided the election, as it always is.

As it stands right now, Hillary has a huge lead in both regular delegates and super delegates. Unless something shifts dramatically, and Sanders wins huge blowouts in state after state, there isn't any way for him to make up the difference. They will both add to their current numbers as each state votes.

Bernie will need to do very well to catch up, so he's a long shot, but he's certainly not out of the running. If he scores a few upsets and the momentum shifts more strongly towards him, anything is possible. Here's an objective but discouraging look at the challenge Bernie faces if he wants to have a majority of elected delegates:

http://fivethirtyeight.com/features/its-really-hard-to-get-bernie-sanders-988-more-delegates/

The 980 doesn't include the Washington delegates yet to be "officially" awarded through the county and state convention processes.

To win a majority of PLEDGED delegates, Sanders must win 56-57% of the delegates henceforth.

...which is the chance given to him by the "experts" of winning the state of Michigan, which he did.