Having suffered chronic pain for months with no hope of a cure, you jump at the chance to finally feel better. You take the tonic for a month, and though you don't notice any change you take comfort in the fact that the salesman told you that it could take some time to begin working. As luck would have it, just as you are shaking the last drops from your bottle, you get word that the salesman is back in town. You rush to his stand to refill your supply of the miracle drug.
When you arrive, however, there seems to be a bit of commotion. The salesman's assistant is doing his best to restrain a young man near the front of the crowd.
"It's all lies!" the young man shouts. "This man promised my sister a cure and his snake oil killed her!"
Concerned that the young man will scare the salesman off, keeping you from acquiring your next dose of the tonic, you and a few others in the crowd help the assistant restrain the young man and move him away from the gathered crowd.
"You have to help me," the young man turns to you. "Let me go back and tell them the truth. I'm a doctor. I can help you if you're sick."
Angry at the audacity of the young man, you snap at him, "How can you discredit that great man. He has cured me of my chronic pain! Now, be gone! No one here needs your kind of medicine."
You stomp back to the salesman's cart, all the while fuming over the young man who nearly cost you the next month's supply of your cure. True, it really hasn't begun to work yet, but it will soon. You have no doubt of that...
Now imagine that the salesman is the GOP. For years you have been eating up their brand of big government solutions to small government problems as the only real cure for America's problems. You are the GOP voters.
The screaming young man is the Tea Party - hated by the snake oil salesman (the GOP) because, as a legitimate doctor, he has the ability to expose him for what he really is, and hated by the patients (you, the voters) who bought the snake oil and would prefer not to see it proven that they have been made to look foolish by a fraud and a cheater.
The problem is that the screaming young man is right. But no one hates the real practitioner more than the snake oil salesman and the people he has fooled.