Agreed that a solid understanding of SEO would be necessary to get a good, solid flow of organic traffic.
Having supported myself through adsense before, its possible but its rare. Its also just not reliable. People fall out of favor- I've seen people lose their houses, lifestyles etc because they became so comfortable with money from adsense and then had it revoked or just lost traffic because people tired of them. I think unless you really take off and are able to keep yourself relevant, i'd just keep your hubpage as nice "fun money".
Granted everything comes with a risk, and if youre a great writer and interesting then of course its possible. But...you would need at the minimum 200,000 views or so a week to get near 500/week
Also know that 1099 income is HEAVILY taxed- more so than traditional income. Youre going to need to claim it and theres no getting around it since its all recorded (I also know people who tried to stupidly hide it, terrible idea). Self employment tax, higher SS tax and medicare taxes, income and state etc.
It can be very comfortable and rewarding, but it wont be for most