It is grossly incorrect to blame Romney for ObamaCare and totally untrue to think that he did anything that is not conservative - in fact conservatives applauded the plan (before ObamaCare was even invented).  

Yet this is an issue that has created doubts in the minds of conservatives - but if they knew the facts there would be an understanding that would have them admire what he did, know that he used solid conservative principles, and know that he is the one who can do something about the ObamaCare mess!

To say ObamaCare was caused or designed after RomneyCare is like saying a Studebaker was designed after a Chevy.  They may both be cars, but it matters what's actually in them.  And if they both have tires, that does not mean they were the same or that the Chevy caused the Studebaker. 

Let's first make a key distinction:  it is sloppy thinking to call the Massachusetts Health Care Bill "RomneyCare", since he did not accept a number of items that were forced in by the 85% Democratic legislature, plus the courts added in some items.

So, we need to remove what the legislature overrode if we are to see what RomneyCare (which would be what would have happened if his vetoes worked and he didn't have an 85% Democratic legislature) actually is. 

He insisted on no new taxes.
He vetoed any employer fees.  (Legislature overrode it.)
He insisted on a free market.  (That part was accepted.)
There was no change in health insurance held already by the insureds.
There was no government run program.
The cost was less than 1% of the state budget.   Cost neutral or close to it.

The only "mandate" that Romney put in was a cost sharing provision for "free riders"; he vetoed any fees for businesses (the 85% Democratic legislature overrode).  This is dramatically different than ObamaCare.

See the RomneyCare Compared To ObamaCare

See and watch the included videos in the link to Health Care Reform


Required employers to provide health care insurance, burdened with extra costs, which costs jobs, of course.
Taxes:  3.8% extra for people over $250K income (most people don't know of this)
           Medical equipment, even on tanning beds 
           Taxes for 10 years and spends for 6 years, in order to misrepresent costs and a false breakeven
Took $500 billion from Medicare
Took  $370 billion from doctor reimbursements (then later, separately, gave back the "doc fix", after using the
     moneys to  "pay for" ObamaCare so that it would be deficit neutral [a real fooler!]
Mandates what the insurance has to be  
RomneyCare:  70 pages,  ObamaCare:  2700 pages 

The damage, I think, is clearly stated in Health Care and Health Insurance on another site.  Good video by Paul Ryan on True Cost Of ObamaCare.   Also, a good video at the conference with the President: Hiding Spending  Doesn't Reduce Spending. and on what has to be in insurance. and in the House This Bill Is A Frankenstein:  Let's Defeat This Bill!    

A new poll by the Harvard School of Public Health and The Boston Globe finds 63% of Massachusetts residents support the health care reform legislation enacted in 2006, 21% oppose it while 6% are not sure and 9% have not heard or read about the law. The percentage of residents supporting the law has increased since a 2009 poll (53%).[1] Support for the law varied by party affiliation, with 77% of Democrats, 60% of Independents, and 40% of Republicans saying they support the legislation. The poll was conducted May 24-26, 2011.

Despite a difficult financial environment in the state, the poll found that 74% want the law to continue, with 51% favoring continuing it with some changes and 23% continuing it as is. Only 9% of state residents favored repealing the health reform law. There has been virtually no change in those wanting to repeal the legislation since the 2009 poll (10%).   Source

Health Care Reform - Some interesting videos of speeches on it, so you'll know what is going on.