The key would be what is their lifestyle. There are people who make hundreds of thousands of dollars and are still financially unstable. There are also people who make $20,000 a year who are happy, content, and secure. My guess would be that few people earning under $15,000 could say that but I am sure their are exceptions.
If things don't change in the next couple days - it won't matter, because the dollar could crash in value. Most folks aren't aware that we are in so much debt - it is virtually impossible for us to ever recover. We may all wake-up one day to find that our bank accounts and 401k accounts are full of worthless dollars. All our politicians are either idiots or crooks (both parties).