That is a great tool. If I am reading the "Target" line right, it looks like Bernie should win Maine today and Michigan on Tuesday(?).
Edit: looking at the contests completed so far, these numbers also seem to suggest that Bernie's been performing worse than he should have in 12 of the 18 states. And in the 6 he did better than 538 predicted, he got four or fewer extra pledged delegates over Hillary.
Edit again: looking at the numbers more, it looks like 538 sees Bernie's biggest estimated gain over Hillary is 17 pledged delegates in Washington. Hillary's biggest estimated gain is in Florida: 18 over Bernie. The swing in the rest of the states are all in the range of a dozen or less (e.g., Bernie's expected to win California and New York, but only gain 3 pledged delegates over Hillary each time; Hillary is supposed to win Illinois and that will get her 13 over Bernie). Oniya's link really highlights how once you fall behind by a few hundred delegates, the proportionate allocation becomes vicious. A lesson which, if memory serves, Hillary learned against Barack in 2008.
And agreed, Mith. I always though Bernie got into the race in the first place to pull Hillary to the left--i.e., he wasn't expecting to win. In terms of the first goal, he's definitely done that.