>>1
It's an interesting question but here's my argument as to why it would change nothing:
Premise: While individuals may make terrible economic decisions, groups make good economic decisions.
Factoid: The rate at which people vote in most democracies tends to increase with their wealth. In America, 13% are at the poverty line or below, and 3% make 100k per year or more, yet 75% of the 100k+ vote in every election, while only about 10% of those at or below the poverty line do. (all stats from wikipedia :P)
Conclusion: Since the poor view voting as essentially valueless (a decision with no economic cost that only 1 in 10 engage in? Therefore it could be said that the poor estimate the probability of benefit from voting having even marginal economic value is 10%), increasing the value of their votes is just multiplying zeroes... or near-zeroes.