Startup Idea : Bounty-based, reversed crowdfunding

Something like ideaswatch + kickstarter. On typical crowdfunding site you post your project and wait for money. Here is what I call reversal: There are two phases: in first, visitors post their ideas and needs or browse those created by others. They can also put any amount of money into escrow, saying: I'm paying this much to someone, who will solve this problem. Second phase is typical crowdfunding campaign. And here is my idea (probably wrong, but maybe you can thing of something better) how transition occurs: you can set your campaign and declare it as solving this particual pain. Then people engaged in putting their money into this pain vote (votes should have some weight based on money) and if, for example, 75% of them votes 'yes', money is transfered to the campaign.