Actually, if you go back to pre-ACA a large majority of the voters, Democratic and Republican, were in favor of health insurance reform that would cover pre-existing conditions and contain costs. It was only after Democrats in congress actually did it, that Republicans demonized it. Before that, they mostly endorsed it, to the extent that Romney implemented it in Massachusetts. That program was working well, and the only people screaming about it were the same libertarians who wanted to get rid of Social Security and Medicare.

The solution they arrived at had a huge amount of Republican input and a huge amount of Big Insurance and Big Pharma input as well. Some would say it was a Republican plan.

All the Republican opposition was thinly-veiled racism (and often not so thinly-veiled) to serve their partisan interests. They generated almost all of the opposition with there Right Wing Noise Machine, and that has been verified many times by insiders who participated.