idea

I think a way of promoting the idea of National Healthcare across to the average American is to present the idea that insurance premiums are already a kind of a privatized system of taxation (for instance, the subject of your video pays $7200 a year in the "taxes", which doesnt include things such as deductables, co-pays, and prescriptions). Admittedly, this tactic may not work well, since technically health insurance is "voluntary".
Perhaps a better way would be to work up a budget and a set of tax tables letting the average American know exactly what they might be paying. Right now while people are doing their taxes and so quite aware of how much money they are sending out could be a good time to do such a thing. I dont know what the rates would be, but I would suspect that they will be lower than many people's current insurance costs (I figured mine to be about $8000 plus for a family of four - surely my tax rate for "socialized medicine" wouldnt be over 10%). Make sure that when people figure their tax rate, they consider it compared to (or rather, instead of) to their current insurance premiums, otherwise it just looks like an additional expense, rather than a savings.
If this post seems a little slip-shod, I apologize. Perhaps I'll rework it and repost it later. I'd also like to point out that the above graphic came from what appears to be an insurance industry website, so bear that in mind.