Even though the race for the Democratic Nomination is winding down, there are still 6 primaries left to contest. While there hasn't been the same abundance of polling in the remaining states as we've seen in places like Pennsylvania, Ohio, Texas, and North Carolina, there has been at least one recent poll in 5 of those states. Based on the polls, today's primary in West Virginia looks to be a blowout in Clinton's favor. If you average the four surveys released in May from that state, you get a 61-24% advantage for Clinton. If you allocated the pledged delegates accordingly, Clinton would receive 20 delegates compared to 8 for Obama (a net gain of 12).
You can see the estimates for West Virginia and the other 5 states here:
On May 20th, the polls estimate that Obama and Clinton will split Oregon and Kentucky, with Clinton taking 3 more pledged delegates than Obama. The one state without a poll is Montana, where Obama is expected to fare well. Overall, Clinton should pick up between 122 and 124 of the remaining pledged delegates while Obama should accumlate between 93 and 95.
So, how close is Obama to actually hitting that magic number? The figure below starts with Obama's delegate (both elected and superdelegates) support as of this morning and then adds to that total the projected elected delegates he would pick up in each state (assuming an 8-8 split in Montana). As I estimated back in March, May 20th is the magic date when Obama will have a majority of the elected delegates. If he doesn't pick up one more superdelegate between now and May 20th (which is obviously very unlikely), he will be about 100 delegates shy of the 2025 figure he needs to clinch the nomination (assuming you don't include Michigan and Florida). If he didn't pick up a single superdelegate between now and June 3rd, he would end up just 66 delegates shy of the magic number.
Even though Obama has picked up at least 25 superdelegates in the past week, it seems unlikely that another 100 would endorse between now and next Tuesday. Nevertheless, I'm sure his campaign is working hard to accumulate enough superdelegates so that he will clinch the nomination after winning a state's primary rather than doing so when some unknown DNC official pledges his/her support on some random Thursday in June. It will be interesting to see how this all plays out, even if we do already know who the winner is going to be.