From the FR thread to which you linked re: the comparison to RR's reported 30% positive, 70% negative rating in 1980 vis a vis Trump in April, 2016:
"Seven in 10 people, including close to half of Republican voters, have an unfavorable view of Donald Trump. "Six in 10 people have an unfavorable view of Ted Cruz even though the liberal media has not started its campaign of destruction against the Texas senator."
I read his quote to say that Cruz has less negative ground to make up than does Trump.
Do your read this the same way?
FReegards!