The United States presidential voting system of the Electoral College gives more voting power to states with higher populations and in particular states in the US the electoral vote doesn't have to represent the popular vote but can represent a substantial influence on who is elected. This means that the few states with the highest population, and higher number of electorates in the Electoral College, ultimately have more power to select the president. In some ways this makes where you live more important that your vote, and this has lead to presidents not winning the popular vote but winning the election for president four times.
This not only makes the process more convoluted but also makes the system less fair, and although the popular vote and the Electoral College vote often go hand in hand, it can lead to people think their vote won’t matter as a result of where they live. It also creates a policy issue, were many rural American’s that may be less represented in the Electoral College system feel that national policies that are decided upon represent more of the more populous urban populations that do not understand their way of life, outlook or economic situation. The effect that this can have is massive voter apathy, diminished voter understanding, undermining faith in voting, effecting turnout and ultimately feeding into a democratic deficit and furthering a rift a mixed society like the United States.