Not sure why so many here can't separate McCain from his war record.
He's an absolutely awful Senator and Republican who served his country. You don't need to be against both to hold a righteous opinion about him.
Cruz is not going to denigrate his war record. Trump has that pleasure because he knows he's not going to get the nod but he's doing great work bringing all these nasty topics to the forefront so the candidates are forced to address (or not) them.
Cruz has handled this the best by far. Trump has the right to say what he thinks/feels. Cruz refocuses on the topics at hand, not the people and personalities that bring them to light.
Cruz it or lose it.