When will Hillary drop out?
By my calculations, Hillary won in Indiana by only 1.46% and lost in North Carolina by 14.81% or essentially 15%. That was a fairly weak showing. She should have been able to do better in both. The only bright spot is that she actually could have done a lot worse in North Carolina and only by campaigning vigorously in recent weeks did she "gain" enough to lose by "only" 15%. My estimate had been that she would have to lose in Indiana by over 10% and lose in North Carolina by over 15% and she did somewhat better than that overall, so she is technically still in the race. Still, given that she was unable to spurt ahead of Barack, the question remains of what it is going to take to convince her to drop out.
Actually that is an easy question to answer... Hillary will drop out when the money runs out, but as long as people continue to throw enough money at her to mount a moderately strong campaign there is no reason for her to drop out. Sure, people will chant something about "unity", but that is not really a factor until after the convention.
Although the Clintons can self-finance Hillary's campaign, it is her success or lack thereof at fundraising that will persuade superdelegates and party officials to support her or abandon her.
The bottom line is that it ain't over until it is over. And it can't be over until Barack figures out how to "close the deal." Sure, a 15% margin of victory is very significant, but why isn't he able to push that up to 20%, 25%, 30% or more? It is not quite clear what he is missing, but he is missing something.