The chart above shows the trend in the “would-never-vote-for” percentage for each of five remaining Republican candidates over this period. This percentage increases for every candidate. The percentage unwilling to consider Kasich rises from 33% to 44%, Rubio from 35% to 39%, Carson from 39% to 47%, Cruz from 41% to 46%, and Trump from 51% to 55%. The main effect of the nomination campaign has been to increase hard core opposition to Republican candidates.

It’s hard to win an election when almost half of the voters start out unwilling to consider voting for you. The best any Republican candidate does is Rubio, and, for him, nearly two out of every five voters still say “no chance.” In contrast, Democratic candidates are not making things worse for themselves. In December of 2015, 38% of respondents said they wouldn’t vote for Bernie Sanders and in February that percentage still stands at 38%. Hillary Clinton started with high negatives—48% in December—but these have fallen slightly to 47%. In short, Democrats are having a vigorous campaign that has, so far, not hurt their candidates’ chances, while Republicans have been destroying one another.