No. You merely need a bigger white voter turn out and a higher percentage of the white vote. What you do is use the border wall and illegal immigrant crime as a wedge issue to get the white vote out.
Blowing off 17% of the population is not a winning strategy.
Blowing off 77% of the population(whites) is an even Less winning strategy.
When you take Hispanics that describe themselves as white out of the mix you are down to 62%. And just because you are not denigrating a group doesn't mean you are blowing off another group. Cruz is anti-illegal immigration without the high negatives.