Well, if the candidates attack Trump, over Hillary, that wouldn’t be smart....and would certainly be an easy thing for Trump to turn around.
I think it is a golden opportunity to sink Hillary’s boat. They should demonstrate how good they will be taking der Hildebeast on. In fact, they should start the debates with a bold display of unison with handshakes and a unified statement that says, “Our dispute is not with each other, but with Hillary Clinton! We have decided to make this forum a joint effort for the education of the public on who we are and who is it we oppose.”