Digging a little deeper on those numbers though 64% of respondents planning or open to voting Democratic this fall support it with only 22% opposed. The overall numbers are negative only because of 94/1 opposition among folks who have said there is no way they'll vote Democratic this fall.
Roughly a third of Americans plan to almost always vote for Democrats, and a third plan to almost always vote for Republicans. Given how the Republican Congressional leadership has decided to wage an all-out war on Democrats' health care bill, it is not surprising that the Republican base is nearly unanimously against it.
The incredibly strong opposition to health care reform in the Republican base makes bipartisan reform next to impossible. I doubt any Republican in Congress would ever want to go completely against their entire base to help Democrats achieve a big victory. Combined with the fact the obstructionism has turned into such a successful political strategy, there seems to be zero incentive for Republicans to help Democrats pass health care reform. A successful bipartisan health care bill would probably hurt Republican chances of taking back Congress. It just won't happen.
With the Republican base firmly opposed to reform, the idea that adding any number of “Republican solutions” to health care reform could increase support with core Republican voters is a foolishness. You have a chicken-and-egg problem. The Republican base might be made slightly more open to reform if there were huge buy-in from Congressional Republicans, but a large number of Congressional Republicans would never buy in to a big, unpopular bill opposed overwhelmingly by their base.
The only real chance for Democrats to improve the standing of health care reform is to increase support with their base, and swing voters who would at least consider voting for Democrats. Provisions like a public option and Medicare buy-in appeal strongly to this group. Clearly, months of trying to move the bill to the right has only eaten away support from the left, and done nothing to improve health care reform's standing with the Republican base.