EDIT: Since I don't want to reply to everyone individually:
I am not condoning prostitution as a career. I am saying that criminalizing prostitution hurts all parties involved. There is a common misconception that wanting to repeal a law means you support whatever that law outlawed. I don't think prostitution should be illegal.
The rule of law is not a place to push morality. There is no reason for the government to interfere in a consensual transaction between two people. If a pimp is forcing a prostitute to sell themselves, that's called slavery, and it is illegal. Selling a prostitute to someone else against their will is illegal, and it is called human trafficking. Simply selling your body harms no third party against their will.