What does it take for Senator Clinton to win the majority of the elected delegates to the Democratic Convention?  <a href=http://en.wikipedia.org/wiki/Democratic_Party_(United_States)_presidential_primaries,_2008”  Wikipedia </a> has a good tabulation of delegates selected so far in the primary process.  To date, the total elected delegates are:  Clinton - 1219, Obama - 1362, with 67 either unallocated or allocated to candidates no longer in the race.  So, Obama has a 143 delegate lead in elected delegates, as of now.

There are still 538 delegates to be elected in the Wyoming, Mississippi, Pennsylvania, etc. elections/caucuses.  (Florida and Michigan not included in the totals.)  Delegates are awarded roughly proportional to the votes each candidate gets.

In order for Senator Clinton to gain 144 delegates on Obama, thus leading in elected delegates, she needs to win the remaining elections/caucuses by an average of 57% to 43%, and that assumes all 67 of the unallocated delegates go to Clinton.  If those are split 50-50, Clinton needs to win by about 63% to 37%.  This is certainly possible.

It is also possible for a comet to strike the Earth next year.

If Obama makes a mistake comparable to endorsing McCain for President, Clinton stands a good chance.  But, Senator Clinton has preempted him in doing that, so even that might not be enough.

If Florida and Michigan are able to get their ducks in a row and select delegates in a manner that complies with the party rules they agreed to, this analysis is slightly different, but unless Clinton wins a huge percentage of the delegates in both states the results are about the same.