Well-off and up get to vote.
Broke: 0$ Poor: 1-9$ Well-off: 10-19$ Rich: 20-49$ Filthy Rich: +50$
Marriage combines salaries of spouses, wealth of a couple is determined by total wages divided by 2. Children, I don't remember how they effect the wealth of a family, either 5$ each or another full person to divide by.

You can play to have a majority of your population be poor. You just need to decide which jobs are important enough to give a higher budget and wage. Maybe force people to marry and have children. Cater services to the well-off and better, give the poor the bare minimum of necessities.