Because, against any and all evidence, people seem to believe that the conservatives are the people to trust with money. Not necessarily with anything else, but with money and war. And right now, money is the most important thing on most people's minds, and what to do about a world that's chronically at least somewhat at war is a close second. So they want conservatives in place who will balance the budget... but not by cutting anything they use... and they don't want to let the conservatives do anything else stupid while they're in there to balance the budget. Which, for the conservatives, is a no-win proposition, since they cannot balance the budget without cutting things people like or raising taxes like they promised not to do. So they only way they can prove they're doing anything at all is to interfere with people's rights in noisy and dramatic ways... which, fortunately, the people don't like either, and are willing to override their representatives outright on the subject.