It's quite likely that the RNC will push the convention delegates to nominate Jeb no matter how poorly he does with the popular vote - i.e. Jeb "loses" every primary and caucus but still gets the nomination. At the very least, they can manipulate the system so that every unpledged delegate votes for Jeb.
I wonder if the RNC has the same kind of “super delegate” votes that the Democrats do. In that case, it really wouldn’t matter what the vote says.