Middle Income earners are a voter group.
The middle class is usually the largest in society. Being in a tax bracket that gives them enough money to tax but not enough to feel secure, middle income earners oppose taxes, especially to their income and properties, and support tax breaks.
Middle income earners aren't predisposed to any other voter groups.
When poor earnings rise above average or high earnings fall below average, the middle class will begin to grow as poor and wealthy people slip into it. Similarly, when middle earnings change, middle income earners will begin decreasing in numbers as they become poorer or richer.
Middle income earners are often very focused on their money; they agree with the capitalists and the wealthy on issues and often oppose socialist initiatives, as they'd largely be the ones paying for them.