ID and WA might be the last states Sanders wins. Not even confident about ID.
After last night, Biden probably wins WA as well.
Based on how CA and CO voted, I'd still bet on Sanders. I don't think a lot of Warren voters will switch to Biden, and I'm still not sure there's enough Not Sanders/Warren vote for Biden to pull out a plurality (since not all voters not in the Sanders/Warren camp will get behind Biden.)
I think it depends quite a lot on what Warren does. Assuming she drops out, if she does not endorse, I'm not sure Bernie benefits much. However, if she does endorse Bernie then he should benefit quite a lot. I think we saw with Pete and Amy that these kind of endorsements DO matter to the supporters.
However, if Warren drops out and endorses Biden, then game over. This is the current panic amongst internet leftists, but I don't for a second believe that this will happen. If Warren drops out she'll either endorse Bernie or she'll stay neutral until the race is effectively decided, like in 2016.