Fred looked out, saw he wasn't getting the votes that could have been going to him, but were diluted by having several other candidates in the race whom the voters considered 'conservative'. He realized that to stay in the race would be futile for him; it was too high a bar to overcome. He wasn't willing to waste any more of his supporters' money to feed his ego.
If you truly had been supporting him, you'd understand that, rather than hold his dropping out against him, and continue dissing him for it.
I was truly supporting him. He is still a quitter.