The best way to win is to never quit.
Your opponents want you to quit. It makes life easier for them. They dread having to deal with you, and your inconvenient opposing point of view. There have been a lot of GBCW's recently. Evan Bayh, for one (LOL). And some here at Daily Kos. It's never a good idea, assuming you actually want to accomplish something, and not give up.
"Eighty percent of success is showing up," Woody Allen said. It's true. Don't give up on that 80%. It's worth it.