Before Obamacare, there was Nixoncare and Romneycare. All three proposed insurance market exchanges, mandatory participation and subsidies for lower income individuals.
Interestingly, in its Romneycare iteration, it was actually proposed by the Heritage Foundation, historically the most influential conservative think tank, and was implemented by Romney when he was the Republican governor of Massachusetts. It is astonishing, therefore, that Obamacare is currently perceived as a Liberal program.
Even more astonishing is how the Heritage Foundation justified its support for this program in its Romneycare generation. The Heritage Foundation places great value on the notion of individual choice, a position they use to oppose all manner of regulations that restrict individual (and corporate) choice. It is difficult to understand, therefore, how the Heritage Foundation supported a government mandate that forced individuals to buy health insurance.
In a feat of rhetorical acrobatics, the foundation recharacterized "individual choice" as "personal responsibility" and argued that forcing personal responsibility through statute and regulation was consistent with the principles and the notion of individual choice. That's a hard argument to buy.
The reality is that the Heritage Foundation was trying to save the struggling private health insurance industry through a subsidy of sorts (making people buy what they didn't feel they needed). The argument was that the program was protecting the insurance free market. The problem is, of course, that if you have to subsidize the industry, then it's not a free market. Moreover, the private healthcare industry has never been a free market.
In the end, this system hurt the middle class and small businesses the most. The true beneficiary of this mish-mosh of a healthcare program is the healthcare industry.
Brill, Steven, America's Bitter Pill: Money, Politics, Backroom Deals and the Fight to Fix our Broken Healthcare System , Random House 2015
Starr, Paul, The Social Transformation of American Medicine , Basic Books 1982 (winner Pulitzer Prize 1984), pages 411-413.