Yes, being poor dramatically increases the chance you will be murdered. Especially poor in the city vs rural. I guess in a city you are more likely to run into someone you need to kill.
I’ve seen stats of cities who break down their crime rates by income level, and the murder rate is almost all poor.
Even in Chicago which has a very high murder rate, you can see it is certain areas that are the worst, and a little bit away there is almost nothing, and certain areas with no murders at all. This site breaks down the Chicago stats. http://heyjackass.com/