"Sign this petition if you want Michelle Obama to be president! If at least 100million people sign, you promise to vote for her. Otherwise, you'll get a $1 gift card to Target."
How would that promise be enforced?
If me and my friends didn't want Michelle Obama to be President, wouldn't it be smart of us to all sign up and take money from an Obama supporter and then vote for who we really want?
It's certainly a new idea.
I think the reasons it might not work would also vary across potential problems they are trying to solve. What are the incentives that have led to the current state? Do people *actually* want to solve the problem?