The thing is, I don't think that most people understand their particular party's rules regarding the nomination process.  As an example, many democrats were outraged when Hillary Clinton got more delegates than she deserved (super delegates).  As far as the republicans go, most probably don't realize that there is a difference between dropping out of the race vs. suspending their campaign.  The delegates that Marco Rubio(169), Ben Carson(8), Jeb Bush(4), Carly Fiorina(1), Mike Huckabee(1) and Rand Paul(1) currently hold still belong to them by virtue of them suspending their campaigns rather than dropping out.  If they completely drop out then their delegates become "super delegates" which means that they can vote for any other candidate.

 

Now here is the other thing that many people don't realize.  Donald Trump does not hold the majority of total republican delegates.  In essence, there are more anti-Trump republicans than there are pro-Trump republicans.  So if this goes to a contested convention, in all likelihood Donald Trump will not be the nominee.

 

Now as far as speculating who would be the eventual nominee, that's a big question.  I would presume either Ted Cruz or Marco Rubio since they currently hold the next most delegates (though Kasich has a chance to add to his).  However, that is only an assumption on my part  regarding pro/anti-Trump delegates.

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