They are the poster child for manic-depressive disorder. One minute they think they are winning and on a delusional high, the next minute they are depressed and ready to slit their wrists.
Remember: the prime mover of all liberals is EGO. They are better than you by every measure and they deserve the best.
You've heard about the 5 stages of grief as formalized by Kubler-Ross. However, unlike someone who has lost a loved one or a terminal patient making good his end, there is no finality to the sense of loss that liberals use as their base motivator. Someone else has their money. Someone else got the break they deserve. Someone else has all the power. And on it goes. There is always some new election or policy debate to rekindle the cycle.
Every time debate begins anew they are thrust back into the Denial-Anger-Bargaining-Depression-cycle. The only stage they can never attain is Acceptance because their sense of loss is never resolved. They still feel cheated/held-down/envious at every turn. Acceptance can only be brought-on by reaching the "Ewe-topian" societal equivalent of the diseased body passing-on to a better place.
Perhaps this explains why they are so eager to shutdown debate and control elections. The see-sawing is emotionally taxing to the already emotionally shallow. Hence their craving for things like "The Fairness Doctrine" and card check and their aversion to things like voter ID laws. If you debate them you only deepen their grief. Since they are flawless it is your ability to debate/vote contrary to their position that is prolonging the inevitable move towards Ewe-topia.
By contrast conservativism anticipates debate. We literally call it "the market place of ideas" and like all true market places we not only expect debate, the competition is welcomed as a means of ensuring the best product for the consumer at the lowest price through the most efficient means of production. Since debate is part of our make-up when it occurs we do not see it as a fault but a virtue and those who are in accord with their virtues tend to be happier...as numerous research papers seem to suggest.