Although it's tempting to just quit to pursue your dream, I would advise against it until you have put your financial life in order and save up some money. It's called a fuck-you fund for a reason.
The idea that you need financial success to do this though is a bit strange. I think it's easier to just quit your job when you're poor from an outside perspective because you're not giving up very much in terms of the grand scheme--you'd throw away a penny before you'd throw away a $20 bill right, but speaking from experience when you're poor, these shit jobs mean a whole helluva lot.
If you live cheaply, saving up a few thousand will allow you do things you'd like to pursue without worrying about money; if you have big house mortgage, fancy car, expensive wife, then giving up a luxury job suddenly becomes not so easy.