People don't vote when they think their vote won't count, or when they don't have time or money to be able to make it to the polls. If we want America truly represented, we need to reform the voting and campaigning processes.
Already in America, the wealthy are more likely to donate to politicians, work on political campaigns, and be in regular contact with elected officials. In addition, politicians are far wealthier than ordinary citizens. These biases already conspire against the interests of poor people.
But deep differences in turnout based on income, age, and race only serve to further reduce the poor’s say. In the status quo, politicians don’t have incentives to listen to ordinary Americans, because it won’t cost them anything. That won’t change until turnout among nonwhite and poor voters increases. There are a number of ways that government can encourage voting: by fixing the Voting Rights Act, by enacting automatic voter registration, by repealing voter ID laws. All would give the poor more voice, and give policies they support a better chance of passage.