Lets see we have one candidate in the race that has 58% of Americans believing that they are not honest and trustworthy. That candidate's only path to the nomination is proving that she's by far the more electable so that party bosses give the nomination to the candidate who is distrusted by the overwhelming majority of the population.
To prove that the other candidate is not electable, the distrusted candidate becomes the stand in for the Republican candidate but the frontrunner can't really make the same case against the the desperate loser because he needs her voters in Novemeber or else the nomination is worthless. This is called political suicide and the idiots remaing nuetral are responsable for this. When one candidate's only motivation is to destroy the frontrunner while the frontrunner can't really fight back for fear of alienating the other supporters with his own "electability argument" this is what you get.