There is no rational basis for any of these candidates to stay in the race.

Ben Carson’s campaign imploded weeks ago. His best showing should have come in Iowa and it did not. He has continued to flounder around. A candidate with so much potential has instead become a whiner because his own campaign committed gross incompetence regarding his trip for clean clothes. Instead of admitting it, he has whined about Ted Cruz all week.

Carly Fiorina has had ample opportunity to shine. But she has repeatedly gotten on debate stages only to enter the witness protection program immediately upon departure from the stage. She never capitalized on any aspect of her campaign and probably will never again be able to get on a debate stage with the top of the field. The race passed her by.

Chris Christie’s impressive murder-suicide with Marco Rubio leaves Christie with nowhere to go. He does not qualify for the CBS debate stage in South Carolina. His polling in South Carolina is more pathetic than his polling in New Hampshire. And he will earn nothing but bitter enmity from GOP pundits for tossing their precious Rubio in Mount Doom.

These candidates need to go and free up debate time for the other candidates to vigorously engage with each other in South Carolina.