I'd say more like 30%. These are the hard core leftists. They never sway, no matter what, because their life line depends on it. They've never worked an honest day in their lives, yet everything is paid for via tax dollars. That includes endowment for the arts as well as once a month regular support checks. Their minds are completely welded closed.
I would agree if you can show that those who work for the endowment for the arts or NPR pay no taxes on their salaries. Lefties pay taxes and they enjoy doing it. Free riders pay no taxes and offer nothing to society. To many people on this site take the 47% who pay no taxes and accuse them directly or indirectly of being free riders. Some are, there is no deny that, but not all.