This would probably be too volatile, and also lack the ability to make deals and compromises. You really need to know that this guy brings this number of votes for at least a certain amount of time, otherwise it becomes very difficult to make deals in a political system.
It would also eliminate the secret ballot nature of the system, because you would have to keep active track of who voted for who, so that that vote could be reassigned at any time. This is an inherent protection against political persecution, so a group in power can't look up the rolls, see who voted against them and move against them. As voting information, it would necessarily be public in order to prevent fraud, at which point other people could look it up. Imagine people in...certain areas...which vote for the 'wrong' party, now their vote can be known by their neighbors.
Well they're right...they live basically in the middle of the west.