The 51 senate votes thing is weird. Thats just taking fact of an arcane rule where bills done through reconciliation cannot be filibustered and only require 50 votes to pass, but every provision in the bill has to have a federal budget line item impact which is unlikely in a single payer bill. I assume the article also realizes the dems would have to take a majority position in the house to even get a bill up to be reconciled.
It also ignores the fact that the healthcare lobby does NOT want single payer, it would essentially wipe out huge chunks of the industry and their leeching of government funds from the system, and so they will spend BILLIONS lobbying Congress to kill it. When one of the rising stars of the democrats, Senator Cory Booker, is against importing medicine from Canada because "is it safe?" you know healthcare has a lot of hidden influence.
Still, its a great idea and I do hope sometime in the next 20 years we get single payer passed. I think the impetus will come from business, its still viewed as a competitive advantage by some but more and more I think businesses realize that getting the fuck out of dealing with healthcare and just assuming every citizen is taken care of is far better than the mess we have now.