According to CBS, the current pledged delegate counts are the following:

Obama, pledged: 1403
Clinton, pledged: 1236

In total, there are 3253 pledged delegates.  This means that there are 614 pledged delegates who are currently unaccounted for.

Let's assume that each candidate will get roughly half (which doesn't seem like an awful assumption) - 307.

That means that at the end of the primaries, the pledged delegate count will be approximately:

Obama: 1710
Clinton: 1543

Again according to CBS, the current superdelegate counts are:

Obama: 213
Clinton: 249

Which brings us to:

Obama: 1923
Clinton: 1792

A candidate will need at least 2025 votes to wrap it up.  Which means:

Obama needs 102 more superdelegates
Clinton needs 233 more superdelegates

There are a total of 795 superdelegates, 462 of which have already expressed a preference.  Leaving 333 superdelegates currently available.

Which means:

Obama needs 30.6% of the remaining superdelegates.

Clinton needs 70.0% of the remaining superdelegates.