The main objective of the democracy is to have everyone have the same rights. The poor can vote, express ideas and be a member of the society in the same ways the rich can.
In reality, this isn't the case. But let me ask you this question; why should it be? The rich have more leverage on the society -money-, therefore can have more influence and, by (in most of the cases) having a high specialization/education, can make the world benefit more than the poor. But this way of thinking leads to denigrate the poor. We should find an adequate middle, where the rich should contribute to the education and knowledge increase of the "poor", so they can help society grow.