the democrats are trying to position themselves as the saviours of obamacare. like everything else, what they're doing is restricting the spectrum: you can have obamacare (the heritage institute plan is on the left in this restricted spectrum) or you can have a free market (which is the right). that's the spectrum.
but, it's a shell game, anyways, because the democrats brought in obamacare in order to sabotage single-payer in the first place, in collusion with the republicans, who are in the employ of crony capitalists that don't want a free market, anyways.
the reality is that healthcare in the united states is a bipartisan consensus around the aca, and it's not going to be modified by anybody for decades.
the democrats are the face of obamacare and will be for years into the future. it's not some accident. if you want single payer, you'll need to put a different party in office.